xref: /linux/drivers/dma/xilinx/xilinx_dma.c (revision 257ca10c7317d4a424e48bb95d14ca53a1f1dd6f)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * DMA driver for Xilinx Video DMA Engine
4  *
5  * Copyright (C) 2010-2014 Xilinx, Inc. All rights reserved.
6  *
7  * Based on the Freescale DMA driver.
8  *
9  * Description:
10  * The AXI Video Direct Memory Access (AXI VDMA) core is a soft Xilinx IP
11  * core that provides high-bandwidth direct memory access between memory
12  * and AXI4-Stream type video target peripherals. The core provides efficient
13  * two dimensional DMA operations with independent asynchronous read (S2MM)
14  * and write (MM2S) channel operation. It can be configured to have either
15  * one channel or two channels. If configured as two channels, one is to
16  * transmit to the video device (MM2S) and another is to receive from the
17  * video device (S2MM). Initialization, status, interrupt and management
18  * registers are accessed through an AXI4-Lite slave interface.
19  *
20  * The AXI Direct Memory Access (AXI DMA) core is a soft Xilinx IP core that
21  * provides high-bandwidth one dimensional direct memory access between memory
22  * and AXI4-Stream target peripherals. It supports one receive and one
23  * transmit channel, both of them optional at synthesis time.
24  *
25  * The AXI CDMA, is a soft IP, which provides high-bandwidth Direct Memory
26  * Access (DMA) between a memory-mapped source address and a memory-mapped
27  * destination address.
28  *
29  * The AXI Multichannel Direct Memory Access (AXI MCDMA) core is a soft
30  * Xilinx IP that provides high-bandwidth direct memory access between
31  * memory and AXI4-Stream target peripherals. It provides scatter gather
32  * (SG) interface with multiple channels independent configuration support.
33  *
34  */
35 
36 #include <linux/bitops.h>
37 #include <linux/dmapool.h>
38 #include <linux/dma/xilinx_dma.h>
39 #include <linux/init.h>
40 #include <linux/interrupt.h>
41 #include <linux/io.h>
42 #include <linux/iopoll.h>
43 #include <linux/module.h>
44 #include <linux/of.h>
45 #include <linux/of_dma.h>
46 #include <linux/of_irq.h>
47 #include <linux/platform_device.h>
48 #include <linux/slab.h>
49 #include <linux/clk.h>
50 #include <linux/io-64-nonatomic-lo-hi.h>
51 
52 #include "../dmaengine.h"
53 
54 /* Register/Descriptor Offsets */
55 #define XILINX_DMA_MM2S_CTRL_OFFSET		0x0000
56 #define XILINX_DMA_S2MM_CTRL_OFFSET		0x0030
57 #define XILINX_VDMA_MM2S_DESC_OFFSET		0x0050
58 #define XILINX_VDMA_S2MM_DESC_OFFSET		0x00a0
59 
60 /* Control Registers */
61 #define XILINX_DMA_REG_DMACR			0x0000
62 #define XILINX_DMA_DMACR_DELAY_MAX		0xff
63 #define XILINX_DMA_DMACR_DELAY_SHIFT		24
64 #define XILINX_DMA_DMACR_FRAME_COUNT_MAX	0xff
65 #define XILINX_DMA_DMACR_FRAME_COUNT_SHIFT	16
66 #define XILINX_DMA_DMACR_ERR_IRQ		BIT(14)
67 #define XILINX_DMA_DMACR_DLY_CNT_IRQ		BIT(13)
68 #define XILINX_DMA_DMACR_FRM_CNT_IRQ		BIT(12)
69 #define XILINX_DMA_DMACR_MASTER_SHIFT		8
70 #define XILINX_DMA_DMACR_FSYNCSRC_SHIFT	5
71 #define XILINX_DMA_DMACR_FRAMECNT_EN		BIT(4)
72 #define XILINX_DMA_DMACR_GENLOCK_EN		BIT(3)
73 #define XILINX_DMA_DMACR_RESET			BIT(2)
74 #define XILINX_DMA_DMACR_CIRC_EN		BIT(1)
75 #define XILINX_DMA_DMACR_RUNSTOP		BIT(0)
76 #define XILINX_DMA_DMACR_FSYNCSRC_MASK		GENMASK(6, 5)
77 #define XILINX_DMA_DMACR_DELAY_MASK		GENMASK(31, 24)
78 #define XILINX_DMA_DMACR_FRAME_COUNT_MASK	GENMASK(23, 16)
79 #define XILINX_DMA_DMACR_MASTER_MASK		GENMASK(11, 8)
80 
81 #define XILINX_DMA_REG_DMASR			0x0004
82 #define XILINX_DMA_DMASR_EOL_LATE_ERR		BIT(15)
83 #define XILINX_DMA_DMASR_ERR_IRQ		BIT(14)
84 #define XILINX_DMA_DMASR_DLY_CNT_IRQ		BIT(13)
85 #define XILINX_DMA_DMASR_FRM_CNT_IRQ		BIT(12)
86 #define XILINX_DMA_DMASR_SOF_LATE_ERR		BIT(11)
87 #define XILINX_DMA_DMASR_SG_DEC_ERR		BIT(10)
88 #define XILINX_DMA_DMASR_SG_SLV_ERR		BIT(9)
89 #define XILINX_DMA_DMASR_EOF_EARLY_ERR		BIT(8)
90 #define XILINX_DMA_DMASR_SOF_EARLY_ERR		BIT(7)
91 #define XILINX_DMA_DMASR_DMA_DEC_ERR		BIT(6)
92 #define XILINX_DMA_DMASR_DMA_SLAVE_ERR		BIT(5)
93 #define XILINX_DMA_DMASR_DMA_INT_ERR		BIT(4)
94 #define XILINX_DMA_DMASR_SG_MASK		BIT(3)
95 #define XILINX_DMA_DMASR_IDLE			BIT(1)
96 #define XILINX_DMA_DMASR_HALTED		BIT(0)
97 #define XILINX_DMA_DMASR_DELAY_MASK		GENMASK(31, 24)
98 #define XILINX_DMA_DMASR_FRAME_COUNT_MASK	GENMASK(23, 16)
99 
100 #define XILINX_DMA_REG_CURDESC			0x0008
101 #define XILINX_DMA_REG_TAILDESC		0x0010
102 #define XILINX_DMA_REG_REG_INDEX		0x0014
103 #define XILINX_DMA_REG_FRMSTORE		0x0018
104 #define XILINX_DMA_REG_THRESHOLD		0x001c
105 #define XILINX_DMA_REG_FRMPTR_STS		0x0024
106 #define XILINX_DMA_REG_PARK_PTR		0x0028
107 #define XILINX_DMA_PARK_PTR_WR_REF_SHIFT	8
108 #define XILINX_DMA_PARK_PTR_WR_REF_MASK		GENMASK(12, 8)
109 #define XILINX_DMA_PARK_PTR_RD_REF_SHIFT	0
110 #define XILINX_DMA_PARK_PTR_RD_REF_MASK		GENMASK(4, 0)
111 #define XILINX_DMA_REG_VDMA_VERSION		0x002c
112 
113 /* Register Direct Mode Registers */
114 #define XILINX_DMA_REG_VSIZE			0x0000
115 #define XILINX_DMA_REG_HSIZE			0x0004
116 
117 #define XILINX_DMA_REG_FRMDLY_STRIDE		0x0008
118 #define XILINX_DMA_FRMDLY_STRIDE_FRMDLY_SHIFT	24
119 #define XILINX_DMA_FRMDLY_STRIDE_STRIDE_SHIFT	0
120 
121 #define XILINX_VDMA_REG_START_ADDRESS(n)	(0x000c + 4 * (n))
122 #define XILINX_VDMA_REG_START_ADDRESS_64(n)	(0x000c + 8 * (n))
123 
124 #define XILINX_VDMA_REG_ENABLE_VERTICAL_FLIP	0x00ec
125 #define XILINX_VDMA_ENABLE_VERTICAL_FLIP	BIT(0)
126 
127 /* HW specific definitions */
128 #define XILINX_MCDMA_MAX_CHANS_PER_DEVICE	0x20
129 #define XILINX_DMA_MAX_CHANS_PER_DEVICE		0x2
130 #define XILINX_CDMA_MAX_CHANS_PER_DEVICE	0x1
131 
132 #define XILINX_DMA_DMAXR_ALL_IRQ_MASK	\
133 		(XILINX_DMA_DMASR_FRM_CNT_IRQ | \
134 		 XILINX_DMA_DMASR_DLY_CNT_IRQ | \
135 		 XILINX_DMA_DMASR_ERR_IRQ)
136 
137 #define XILINX_DMA_DMASR_ALL_ERR_MASK	\
138 		(XILINX_DMA_DMASR_EOL_LATE_ERR | \
139 		 XILINX_DMA_DMASR_SOF_LATE_ERR | \
140 		 XILINX_DMA_DMASR_SG_DEC_ERR | \
141 		 XILINX_DMA_DMASR_SG_SLV_ERR | \
142 		 XILINX_DMA_DMASR_EOF_EARLY_ERR | \
143 		 XILINX_DMA_DMASR_SOF_EARLY_ERR | \
144 		 XILINX_DMA_DMASR_DMA_DEC_ERR | \
145 		 XILINX_DMA_DMASR_DMA_SLAVE_ERR | \
146 		 XILINX_DMA_DMASR_DMA_INT_ERR)
147 
148 /*
149  * Recoverable errors are DMA Internal error, SOF Early, EOF Early
150  * and SOF Late. They are only recoverable when C_FLUSH_ON_FSYNC
151  * is enabled in the h/w system.
152  */
153 #define XILINX_DMA_DMASR_ERR_RECOVER_MASK	\
154 		(XILINX_DMA_DMASR_SOF_LATE_ERR | \
155 		 XILINX_DMA_DMASR_EOF_EARLY_ERR | \
156 		 XILINX_DMA_DMASR_SOF_EARLY_ERR | \
157 		 XILINX_DMA_DMASR_DMA_INT_ERR)
158 
159 /* Axi VDMA Flush on Fsync bits */
160 #define XILINX_DMA_FLUSH_S2MM		3
161 #define XILINX_DMA_FLUSH_MM2S		2
162 #define XILINX_DMA_FLUSH_BOTH		1
163 
164 /* Delay loop counter to prevent hardware failure */
165 #define XILINX_DMA_LOOP_COUNT		1000000
166 
167 /* AXI DMA Specific Registers/Offsets */
168 #define XILINX_DMA_REG_SRCDSTADDR	0x18
169 #define XILINX_DMA_REG_BTT		0x28
170 
171 /* AXI DMA Specific Masks/Bit fields */
172 #define XILINX_DMA_MAX_TRANS_LEN_MIN	8
173 #define XILINX_DMA_MAX_TRANS_LEN_MAX	23
174 #define XILINX_DMA_V2_MAX_TRANS_LEN_MAX	26
175 #define XILINX_DMA_CR_COALESCE_MAX	GENMASK(23, 16)
176 #define XILINX_DMA_CR_DELAY_MAX		GENMASK(31, 24)
177 #define XILINX_DMA_CR_CYCLIC_BD_EN_MASK	BIT(4)
178 #define XILINX_DMA_CR_COALESCE_SHIFT	16
179 #define XILINX_DMA_CR_DELAY_SHIFT	24
180 #define XILINX_DMA_BD_SOP		BIT(27)
181 #define XILINX_DMA_BD_EOP		BIT(26)
182 #define XILINX_DMA_BD_COMP_MASK		BIT(31)
183 #define XILINX_DMA_COALESCE_MAX		255
184 #define XILINX_DMA_NUM_DESCS		512
185 #define XILINX_DMA_NUM_APP_WORDS	5
186 
187 /* AXI CDMA Specific Registers/Offsets */
188 #define XILINX_CDMA_REG_SRCADDR		0x18
189 #define XILINX_CDMA_REG_DSTADDR		0x20
190 
191 /* AXI CDMA Specific Masks */
192 #define XILINX_CDMA_CR_SGMODE          BIT(3)
193 
194 #define xilinx_prep_dma_addr_t(addr)	\
195 	((dma_addr_t)((u64)addr##_##msb << 32 | (addr)))
196 
197 /* AXI MCDMA Specific Registers/Offsets */
198 #define XILINX_MCDMA_MM2S_CTRL_OFFSET		0x0000
199 #define XILINX_MCDMA_S2MM_CTRL_OFFSET		0x0500
200 #define XILINX_MCDMA_CHEN_OFFSET		0x0008
201 #define XILINX_MCDMA_CH_ERR_OFFSET		0x0010
202 #define XILINX_MCDMA_RXINT_SER_OFFSET		0x0020
203 #define XILINX_MCDMA_TXINT_SER_OFFSET		0x0028
204 #define XILINX_MCDMA_CHAN_CR_OFFSET(x)		(0x40 + (x) * 0x40)
205 #define XILINX_MCDMA_CHAN_SR_OFFSET(x)		(0x44 + (x) * 0x40)
206 #define XILINX_MCDMA_CHAN_CDESC_OFFSET(x)	(0x48 + (x) * 0x40)
207 #define XILINX_MCDMA_CHAN_TDESC_OFFSET(x)	(0x50 + (x) * 0x40)
208 
209 /* AXI MCDMA Specific Masks/Shifts */
210 #define XILINX_MCDMA_COALESCE_SHIFT		16
211 #define XILINX_MCDMA_COALESCE_MAX		24
212 #define XILINX_MCDMA_IRQ_ALL_MASK		GENMASK(7, 5)
213 #define XILINX_MCDMA_COALESCE_MASK		GENMASK(23, 16)
214 #define XILINX_MCDMA_CR_RUNSTOP_MASK		BIT(0)
215 #define XILINX_MCDMA_IRQ_IOC_MASK		BIT(5)
216 #define XILINX_MCDMA_IRQ_DELAY_MASK		BIT(6)
217 #define XILINX_MCDMA_IRQ_ERR_MASK		BIT(7)
218 #define XILINX_MCDMA_BD_EOP			BIT(30)
219 #define XILINX_MCDMA_BD_SOP			BIT(31)
220 
221 /**
222  * struct xilinx_vdma_desc_hw - Hardware Descriptor
223  * @next_desc: Next Descriptor Pointer @0x00
224  * @pad1: Reserved @0x04
225  * @buf_addr: Buffer address @0x08
226  * @buf_addr_msb: MSB of Buffer address @0x0C
227  * @vsize: Vertical Size @0x10
228  * @hsize: Horizontal Size @0x14
229  * @stride: Number of bytes between the first
230  *	    pixels of each horizontal line @0x18
231  */
232 struct xilinx_vdma_desc_hw {
233 	u32 next_desc;
234 	u32 pad1;
235 	u32 buf_addr;
236 	u32 buf_addr_msb;
237 	u32 vsize;
238 	u32 hsize;
239 	u32 stride;
240 } __aligned(64);
241 
242 /**
243  * struct xilinx_axidma_desc_hw - Hardware Descriptor for AXI DMA
244  * @next_desc: Next Descriptor Pointer @0x00
245  * @next_desc_msb: MSB of Next Descriptor Pointer @0x04
246  * @buf_addr: Buffer address @0x08
247  * @buf_addr_msb: MSB of Buffer address @0x0C
248  * @reserved1: Reserved @0x10
249  * @reserved2: Reserved @0x14
250  * @control: Control field @0x18
251  * @status: Status field @0x1C
252  * @app: APP Fields @0x20 - 0x30
253  */
254 struct xilinx_axidma_desc_hw {
255 	u32 next_desc;
256 	u32 next_desc_msb;
257 	u32 buf_addr;
258 	u32 buf_addr_msb;
259 	u32 reserved1;
260 	u32 reserved2;
261 	u32 control;
262 	u32 status;
263 	u32 app[XILINX_DMA_NUM_APP_WORDS];
264 } __aligned(64);
265 
266 /**
267  * struct xilinx_aximcdma_desc_hw - Hardware Descriptor for AXI MCDMA
268  * @next_desc: Next Descriptor Pointer @0x00
269  * @next_desc_msb: MSB of Next Descriptor Pointer @0x04
270  * @buf_addr: Buffer address @0x08
271  * @buf_addr_msb: MSB of Buffer address @0x0C
272  * @rsvd: Reserved field @0x10
273  * @control: Control Information field @0x14
274  * @status: Status field @0x18
275  * @sideband_status: Status of sideband signals @0x1C
276  * @app: APP Fields @0x20 - 0x30
277  */
278 struct xilinx_aximcdma_desc_hw {
279 	u32 next_desc;
280 	u32 next_desc_msb;
281 	u32 buf_addr;
282 	u32 buf_addr_msb;
283 	u32 rsvd;
284 	u32 control;
285 	u32 status;
286 	u32 sideband_status;
287 	u32 app[XILINX_DMA_NUM_APP_WORDS];
288 } __aligned(64);
289 
290 /**
291  * struct xilinx_cdma_desc_hw - Hardware Descriptor
292  * @next_desc: Next Descriptor Pointer @0x00
293  * @next_desc_msb: Next Descriptor Pointer MSB @0x04
294  * @src_addr: Source address @0x08
295  * @src_addr_msb: Source address MSB @0x0C
296  * @dest_addr: Destination address @0x10
297  * @dest_addr_msb: Destination address MSB @0x14
298  * @control: Control field @0x18
299  * @status: Status field @0x1C
300  */
301 struct xilinx_cdma_desc_hw {
302 	u32 next_desc;
303 	u32 next_desc_msb;
304 	u32 src_addr;
305 	u32 src_addr_msb;
306 	u32 dest_addr;
307 	u32 dest_addr_msb;
308 	u32 control;
309 	u32 status;
310 } __aligned(64);
311 
312 /**
313  * struct xilinx_vdma_tx_segment - Descriptor segment
314  * @hw: Hardware descriptor
315  * @node: Node in the descriptor segments list
316  * @phys: Physical address of segment
317  */
318 struct xilinx_vdma_tx_segment {
319 	struct xilinx_vdma_desc_hw hw;
320 	struct list_head node;
321 	dma_addr_t phys;
322 } __aligned(64);
323 
324 /**
325  * struct xilinx_axidma_tx_segment - Descriptor segment
326  * @hw: Hardware descriptor
327  * @node: Node in the descriptor segments list
328  * @phys: Physical address of segment
329  */
330 struct xilinx_axidma_tx_segment {
331 	struct xilinx_axidma_desc_hw hw;
332 	struct list_head node;
333 	dma_addr_t phys;
334 } __aligned(64);
335 
336 /**
337  * struct xilinx_aximcdma_tx_segment - Descriptor segment
338  * @hw: Hardware descriptor
339  * @node: Node in the descriptor segments list
340  * @phys: Physical address of segment
341  */
342 struct xilinx_aximcdma_tx_segment {
343 	struct xilinx_aximcdma_desc_hw hw;
344 	struct list_head node;
345 	dma_addr_t phys;
346 } __aligned(64);
347 
348 /**
349  * struct xilinx_cdma_tx_segment - Descriptor segment
350  * @hw: Hardware descriptor
351  * @node: Node in the descriptor segments list
352  * @phys: Physical address of segment
353  */
354 struct xilinx_cdma_tx_segment {
355 	struct xilinx_cdma_desc_hw hw;
356 	struct list_head node;
357 	dma_addr_t phys;
358 } __aligned(64);
359 
360 /**
361  * struct xilinx_dma_tx_descriptor - Per Transaction structure
362  * @async_tx: Async transaction descriptor
363  * @segments: TX segments list
364  * @node: Node in the channel descriptors list
365  * @cyclic: Check for cyclic transfers.
366  * @err: Whether the descriptor has an error.
367  * @residue: Residue of the completed descriptor
368  */
369 struct xilinx_dma_tx_descriptor {
370 	struct dma_async_tx_descriptor async_tx;
371 	struct list_head segments;
372 	struct list_head node;
373 	bool cyclic;
374 	bool err;
375 	u32 residue;
376 };
377 
378 /**
379  * struct xilinx_dma_chan - Driver specific DMA channel structure
380  * @xdev: Driver specific device structure
381  * @ctrl_offset: Control registers offset
382  * @desc_offset: TX descriptor registers offset
383  * @lock: Descriptor operation lock
384  * @pending_list: Descriptors waiting
385  * @active_list: Descriptors ready to submit
386  * @done_list: Complete descriptors
387  * @free_seg_list: Free descriptors
388  * @common: DMA common channel
389  * @desc_pool: Descriptors pool
390  * @dev: The dma device
391  * @irq: Channel IRQ
392  * @id: Channel ID
393  * @direction: Transfer direction
394  * @num_frms: Number of frames
395  * @has_sg: Support scatter transfers
396  * @cyclic: Check for cyclic transfers.
397  * @genlock: Support genlock mode
398  * @err: Channel has errors
399  * @idle: Check for channel idle
400  * @terminating: Check for channel being synchronized by user
401  * @tasklet: Cleanup work after irq
402  * @config: Device configuration info
403  * @flush_on_fsync: Flush on Frame sync
404  * @desc_pendingcount: Descriptor pending count
405  * @ext_addr: Indicates 64 bit addressing is supported by dma channel
406  * @desc_submitcount: Descriptor h/w submitted count
407  * @seg_v: Statically allocated segments base
408  * @seg_mv: Statically allocated segments base for MCDMA
409  * @seg_p: Physical allocated segments base
410  * @cyclic_seg_v: Statically allocated segment base for cyclic transfers
411  * @cyclic_seg_p: Physical allocated segments base for cyclic dma
412  * @start_transfer: Differentiate b/w DMA IP's transfer
413  * @stop_transfer: Differentiate b/w DMA IP's quiesce
414  * @tdest: TDEST value for mcdma
415  * @has_vflip: S2MM vertical flip
416  * @irq_delay: Interrupt delay timeout
417  */
418 struct xilinx_dma_chan {
419 	struct xilinx_dma_device *xdev;
420 	u32 ctrl_offset;
421 	u32 desc_offset;
422 	spinlock_t lock;
423 	struct list_head pending_list;
424 	struct list_head active_list;
425 	struct list_head done_list;
426 	struct list_head free_seg_list;
427 	struct dma_chan common;
428 	struct dma_pool *desc_pool;
429 	struct device *dev;
430 	int irq;
431 	int id;
432 	enum dma_transfer_direction direction;
433 	int num_frms;
434 	bool has_sg;
435 	bool cyclic;
436 	bool genlock;
437 	bool err;
438 	bool idle;
439 	bool terminating;
440 	struct tasklet_struct tasklet;
441 	struct xilinx_vdma_config config;
442 	bool flush_on_fsync;
443 	u32 desc_pendingcount;
444 	bool ext_addr;
445 	u32 desc_submitcount;
446 	struct xilinx_axidma_tx_segment *seg_v;
447 	struct xilinx_aximcdma_tx_segment *seg_mv;
448 	dma_addr_t seg_p;
449 	struct xilinx_axidma_tx_segment *cyclic_seg_v;
450 	dma_addr_t cyclic_seg_p;
451 	void (*start_transfer)(struct xilinx_dma_chan *chan);
452 	int (*stop_transfer)(struct xilinx_dma_chan *chan);
453 	u16 tdest;
454 	bool has_vflip;
455 	u8 irq_delay;
456 };
457 
458 /**
459  * enum xdma_ip_type - DMA IP type.
460  *
461  * @XDMA_TYPE_AXIDMA: Axi dma ip.
462  * @XDMA_TYPE_CDMA: Axi cdma ip.
463  * @XDMA_TYPE_VDMA: Axi vdma ip.
464  * @XDMA_TYPE_AXIMCDMA: Axi MCDMA ip.
465  *
466  */
467 enum xdma_ip_type {
468 	XDMA_TYPE_AXIDMA = 0,
469 	XDMA_TYPE_CDMA,
470 	XDMA_TYPE_VDMA,
471 	XDMA_TYPE_AXIMCDMA
472 };
473 
474 struct xilinx_dma_config {
475 	enum xdma_ip_type dmatype;
476 	int (*clk_init)(struct platform_device *pdev, struct clk **axi_clk,
477 			struct clk **tx_clk, struct clk **txs_clk,
478 			struct clk **rx_clk, struct clk **rxs_clk);
479 	irqreturn_t (*irq_handler)(int irq, void *data);
480 	const int max_channels;
481 };
482 
483 /**
484  * struct xilinx_dma_device - DMA device structure
485  * @regs: I/O mapped base address
486  * @dev: Device Structure
487  * @common: DMA device structure
488  * @chan: Driver specific DMA channel
489  * @flush_on_fsync: Flush on frame sync
490  * @ext_addr: Indicates 64 bit addressing is supported by dma device
491  * @pdev: Platform device structure pointer
492  * @dma_config: DMA config structure
493  * @axi_clk: DMA Axi4-lite interace clock
494  * @tx_clk: DMA mm2s clock
495  * @txs_clk: DMA mm2s stream clock
496  * @rx_clk: DMA s2mm clock
497  * @rxs_clk: DMA s2mm stream clock
498  * @s2mm_chan_id: DMA s2mm channel identifier
499  * @mm2s_chan_id: DMA mm2s channel identifier
500  * @max_buffer_len: Max buffer length
501  * @has_axistream_connected: AXI DMA connected to AXI Stream IP
502  */
503 struct xilinx_dma_device {
504 	void __iomem *regs;
505 	struct device *dev;
506 	struct dma_device common;
507 	struct xilinx_dma_chan *chan[XILINX_MCDMA_MAX_CHANS_PER_DEVICE];
508 	u32 flush_on_fsync;
509 	bool ext_addr;
510 	struct platform_device  *pdev;
511 	const struct xilinx_dma_config *dma_config;
512 	struct clk *axi_clk;
513 	struct clk *tx_clk;
514 	struct clk *txs_clk;
515 	struct clk *rx_clk;
516 	struct clk *rxs_clk;
517 	u32 s2mm_chan_id;
518 	u32 mm2s_chan_id;
519 	u32 max_buffer_len;
520 	bool has_axistream_connected;
521 };
522 
523 /* Macros */
524 #define to_xilinx_chan(chan) \
525 	container_of(chan, struct xilinx_dma_chan, common)
526 #define to_dma_tx_descriptor(tx) \
527 	container_of(tx, struct xilinx_dma_tx_descriptor, async_tx)
528 #define xilinx_dma_poll_timeout(chan, reg, val, cond, delay_us, timeout_us) \
529 	readl_poll_timeout_atomic(chan->xdev->regs + chan->ctrl_offset + reg, \
530 				  val, cond, delay_us, timeout_us)
531 
532 /* IO accessors */
533 static inline u32 dma_read(struct xilinx_dma_chan *chan, u32 reg)
534 {
535 	return ioread32(chan->xdev->regs + reg);
536 }
537 
538 static inline void dma_write(struct xilinx_dma_chan *chan, u32 reg, u32 value)
539 {
540 	iowrite32(value, chan->xdev->regs + reg);
541 }
542 
543 static inline void vdma_desc_write(struct xilinx_dma_chan *chan, u32 reg,
544 				   u32 value)
545 {
546 	dma_write(chan, chan->desc_offset + reg, value);
547 }
548 
549 static inline u32 dma_ctrl_read(struct xilinx_dma_chan *chan, u32 reg)
550 {
551 	return dma_read(chan, chan->ctrl_offset + reg);
552 }
553 
554 static inline void dma_ctrl_write(struct xilinx_dma_chan *chan, u32 reg,
555 				   u32 value)
556 {
557 	dma_write(chan, chan->ctrl_offset + reg, value);
558 }
559 
560 static inline void dma_ctrl_clr(struct xilinx_dma_chan *chan, u32 reg,
561 				 u32 clr)
562 {
563 	dma_ctrl_write(chan, reg, dma_ctrl_read(chan, reg) & ~clr);
564 }
565 
566 static inline void dma_ctrl_set(struct xilinx_dma_chan *chan, u32 reg,
567 				 u32 set)
568 {
569 	dma_ctrl_write(chan, reg, dma_ctrl_read(chan, reg) | set);
570 }
571 
572 /**
573  * vdma_desc_write_64 - 64-bit descriptor write
574  * @chan: Driver specific VDMA channel
575  * @reg: Register to write
576  * @value_lsb: lower address of the descriptor.
577  * @value_msb: upper address of the descriptor.
578  *
579  * Since vdma driver is trying to write to a register offset which is not a
580  * multiple of 64 bits(ex : 0x5c), we are writing as two separate 32 bits
581  * instead of a single 64 bit register write.
582  */
583 static inline void vdma_desc_write_64(struct xilinx_dma_chan *chan, u32 reg,
584 				      u32 value_lsb, u32 value_msb)
585 {
586 	/* Write the lsb 32 bits*/
587 	writel(value_lsb, chan->xdev->regs + chan->desc_offset + reg);
588 
589 	/* Write the msb 32 bits */
590 	writel(value_msb, chan->xdev->regs + chan->desc_offset + reg + 4);
591 }
592 
593 static inline void dma_writeq(struct xilinx_dma_chan *chan, u32 reg, u64 value)
594 {
595 	lo_hi_writeq(value, chan->xdev->regs + chan->ctrl_offset + reg);
596 }
597 
598 static inline void xilinx_write(struct xilinx_dma_chan *chan, u32 reg,
599 				dma_addr_t addr)
600 {
601 	if (chan->ext_addr)
602 		dma_writeq(chan, reg, addr);
603 	else
604 		dma_ctrl_write(chan, reg, addr);
605 }
606 
607 static inline void xilinx_axidma_buf(struct xilinx_dma_chan *chan,
608 				     struct xilinx_axidma_desc_hw *hw,
609 				     dma_addr_t buf_addr, size_t sg_used,
610 				     size_t period_len)
611 {
612 	if (chan->ext_addr) {
613 		hw->buf_addr = lower_32_bits(buf_addr + sg_used + period_len);
614 		hw->buf_addr_msb = upper_32_bits(buf_addr + sg_used +
615 						 period_len);
616 	} else {
617 		hw->buf_addr = buf_addr + sg_used + period_len;
618 	}
619 }
620 
621 static inline void xilinx_aximcdma_buf(struct xilinx_dma_chan *chan,
622 				       struct xilinx_aximcdma_desc_hw *hw,
623 				       dma_addr_t buf_addr, size_t sg_used)
624 {
625 	if (chan->ext_addr) {
626 		hw->buf_addr = lower_32_bits(buf_addr + sg_used);
627 		hw->buf_addr_msb = upper_32_bits(buf_addr + sg_used);
628 	} else {
629 		hw->buf_addr = buf_addr + sg_used;
630 	}
631 }
632 
633 /**
634  * xilinx_dma_get_metadata_ptr- Populate metadata pointer and payload length
635  * @tx: async transaction descriptor
636  * @payload_len: metadata payload length
637  * @max_len: metadata max length
638  * Return: The app field pointer.
639  */
640 static void *xilinx_dma_get_metadata_ptr(struct dma_async_tx_descriptor *tx,
641 					 size_t *payload_len, size_t *max_len)
642 {
643 	struct xilinx_dma_tx_descriptor *desc = to_dma_tx_descriptor(tx);
644 	struct xilinx_axidma_tx_segment *seg;
645 
646 	*max_len = *payload_len = sizeof(u32) * XILINX_DMA_NUM_APP_WORDS;
647 	seg = list_first_entry(&desc->segments,
648 			       struct xilinx_axidma_tx_segment, node);
649 	return seg->hw.app;
650 }
651 
652 static struct dma_descriptor_metadata_ops xilinx_dma_metadata_ops = {
653 	.get_ptr = xilinx_dma_get_metadata_ptr,
654 };
655 
656 /* -----------------------------------------------------------------------------
657  * Descriptors and segments alloc and free
658  */
659 
660 /**
661  * xilinx_vdma_alloc_tx_segment - Allocate transaction segment
662  * @chan: Driver specific DMA channel
663  *
664  * Return: The allocated segment on success and NULL on failure.
665  */
666 static struct xilinx_vdma_tx_segment *
667 xilinx_vdma_alloc_tx_segment(struct xilinx_dma_chan *chan)
668 {
669 	struct xilinx_vdma_tx_segment *segment;
670 	dma_addr_t phys;
671 
672 	segment = dma_pool_zalloc(chan->desc_pool, GFP_ATOMIC, &phys);
673 	if (!segment)
674 		return NULL;
675 
676 	segment->phys = phys;
677 
678 	return segment;
679 }
680 
681 /**
682  * xilinx_cdma_alloc_tx_segment - Allocate transaction segment
683  * @chan: Driver specific DMA channel
684  *
685  * Return: The allocated segment on success and NULL on failure.
686  */
687 static struct xilinx_cdma_tx_segment *
688 xilinx_cdma_alloc_tx_segment(struct xilinx_dma_chan *chan)
689 {
690 	struct xilinx_cdma_tx_segment *segment;
691 	dma_addr_t phys;
692 
693 	segment = dma_pool_zalloc(chan->desc_pool, GFP_ATOMIC, &phys);
694 	if (!segment)
695 		return NULL;
696 
697 	segment->phys = phys;
698 
699 	return segment;
700 }
701 
702 /**
703  * xilinx_axidma_alloc_tx_segment - Allocate transaction segment
704  * @chan: Driver specific DMA channel
705  *
706  * Return: The allocated segment on success and NULL on failure.
707  */
708 static struct xilinx_axidma_tx_segment *
709 xilinx_axidma_alloc_tx_segment(struct xilinx_dma_chan *chan)
710 {
711 	struct xilinx_axidma_tx_segment *segment = NULL;
712 	unsigned long flags;
713 
714 	spin_lock_irqsave(&chan->lock, flags);
715 	if (!list_empty(&chan->free_seg_list)) {
716 		segment = list_first_entry(&chan->free_seg_list,
717 					   struct xilinx_axidma_tx_segment,
718 					   node);
719 		list_del(&segment->node);
720 	}
721 	spin_unlock_irqrestore(&chan->lock, flags);
722 
723 	if (!segment)
724 		dev_dbg(chan->dev, "Could not find free tx segment\n");
725 
726 	return segment;
727 }
728 
729 /**
730  * xilinx_aximcdma_alloc_tx_segment - Allocate transaction segment
731  * @chan: Driver specific DMA channel
732  *
733  * Return: The allocated segment on success and NULL on failure.
734  */
735 static struct xilinx_aximcdma_tx_segment *
736 xilinx_aximcdma_alloc_tx_segment(struct xilinx_dma_chan *chan)
737 {
738 	struct xilinx_aximcdma_tx_segment *segment = NULL;
739 	unsigned long flags;
740 
741 	spin_lock_irqsave(&chan->lock, flags);
742 	if (!list_empty(&chan->free_seg_list)) {
743 		segment = list_first_entry(&chan->free_seg_list,
744 					   struct xilinx_aximcdma_tx_segment,
745 					   node);
746 		list_del(&segment->node);
747 	}
748 	spin_unlock_irqrestore(&chan->lock, flags);
749 
750 	return segment;
751 }
752 
753 static void xilinx_dma_clean_hw_desc(struct xilinx_axidma_desc_hw *hw)
754 {
755 	u32 next_desc = hw->next_desc;
756 	u32 next_desc_msb = hw->next_desc_msb;
757 
758 	memset(hw, 0, sizeof(struct xilinx_axidma_desc_hw));
759 
760 	hw->next_desc = next_desc;
761 	hw->next_desc_msb = next_desc_msb;
762 }
763 
764 static void xilinx_mcdma_clean_hw_desc(struct xilinx_aximcdma_desc_hw *hw)
765 {
766 	u32 next_desc = hw->next_desc;
767 	u32 next_desc_msb = hw->next_desc_msb;
768 
769 	memset(hw, 0, sizeof(struct xilinx_aximcdma_desc_hw));
770 
771 	hw->next_desc = next_desc;
772 	hw->next_desc_msb = next_desc_msb;
773 }
774 
775 /**
776  * xilinx_dma_free_tx_segment - Free transaction segment
777  * @chan: Driver specific DMA channel
778  * @segment: DMA transaction segment
779  */
780 static void xilinx_dma_free_tx_segment(struct xilinx_dma_chan *chan,
781 				struct xilinx_axidma_tx_segment *segment)
782 {
783 	xilinx_dma_clean_hw_desc(&segment->hw);
784 
785 	list_add_tail(&segment->node, &chan->free_seg_list);
786 }
787 
788 /**
789  * xilinx_mcdma_free_tx_segment - Free transaction segment
790  * @chan: Driver specific DMA channel
791  * @segment: DMA transaction segment
792  */
793 static void xilinx_mcdma_free_tx_segment(struct xilinx_dma_chan *chan,
794 					 struct xilinx_aximcdma_tx_segment *
795 					 segment)
796 {
797 	xilinx_mcdma_clean_hw_desc(&segment->hw);
798 
799 	list_add_tail(&segment->node, &chan->free_seg_list);
800 }
801 
802 /**
803  * xilinx_cdma_free_tx_segment - Free transaction segment
804  * @chan: Driver specific DMA channel
805  * @segment: DMA transaction segment
806  */
807 static void xilinx_cdma_free_tx_segment(struct xilinx_dma_chan *chan,
808 				struct xilinx_cdma_tx_segment *segment)
809 {
810 	dma_pool_free(chan->desc_pool, segment, segment->phys);
811 }
812 
813 /**
814  * xilinx_vdma_free_tx_segment - Free transaction segment
815  * @chan: Driver specific DMA channel
816  * @segment: DMA transaction segment
817  */
818 static void xilinx_vdma_free_tx_segment(struct xilinx_dma_chan *chan,
819 					struct xilinx_vdma_tx_segment *segment)
820 {
821 	dma_pool_free(chan->desc_pool, segment, segment->phys);
822 }
823 
824 /**
825  * xilinx_dma_alloc_tx_descriptor - Allocate transaction descriptor
826  * @chan: Driver specific DMA channel
827  *
828  * Return: The allocated descriptor on success and NULL on failure.
829  */
830 static struct xilinx_dma_tx_descriptor *
831 xilinx_dma_alloc_tx_descriptor(struct xilinx_dma_chan *chan)
832 {
833 	struct xilinx_dma_tx_descriptor *desc;
834 
835 	desc = kzalloc(sizeof(*desc), GFP_NOWAIT);
836 	if (!desc)
837 		return NULL;
838 
839 	INIT_LIST_HEAD(&desc->segments);
840 
841 	return desc;
842 }
843 
844 /**
845  * xilinx_dma_free_tx_descriptor - Free transaction descriptor
846  * @chan: Driver specific DMA channel
847  * @desc: DMA transaction descriptor
848  */
849 static void
850 xilinx_dma_free_tx_descriptor(struct xilinx_dma_chan *chan,
851 			       struct xilinx_dma_tx_descriptor *desc)
852 {
853 	struct xilinx_vdma_tx_segment *segment, *next;
854 	struct xilinx_cdma_tx_segment *cdma_segment, *cdma_next;
855 	struct xilinx_axidma_tx_segment *axidma_segment, *axidma_next;
856 	struct xilinx_aximcdma_tx_segment *aximcdma_segment, *aximcdma_next;
857 
858 	if (!desc)
859 		return;
860 
861 	if (chan->xdev->dma_config->dmatype == XDMA_TYPE_VDMA) {
862 		list_for_each_entry_safe(segment, next, &desc->segments, node) {
863 			list_del(&segment->node);
864 			xilinx_vdma_free_tx_segment(chan, segment);
865 		}
866 	} else if (chan->xdev->dma_config->dmatype == XDMA_TYPE_CDMA) {
867 		list_for_each_entry_safe(cdma_segment, cdma_next,
868 					 &desc->segments, node) {
869 			list_del(&cdma_segment->node);
870 			xilinx_cdma_free_tx_segment(chan, cdma_segment);
871 		}
872 	} else if (chan->xdev->dma_config->dmatype == XDMA_TYPE_AXIDMA) {
873 		list_for_each_entry_safe(axidma_segment, axidma_next,
874 					 &desc->segments, node) {
875 			list_del(&axidma_segment->node);
876 			xilinx_dma_free_tx_segment(chan, axidma_segment);
877 		}
878 	} else {
879 		list_for_each_entry_safe(aximcdma_segment, aximcdma_next,
880 					 &desc->segments, node) {
881 			list_del(&aximcdma_segment->node);
882 			xilinx_mcdma_free_tx_segment(chan, aximcdma_segment);
883 		}
884 	}
885 
886 	kfree(desc);
887 }
888 
889 /* Required functions */
890 
891 /**
892  * xilinx_dma_free_desc_list - Free descriptors list
893  * @chan: Driver specific DMA channel
894  * @list: List to parse and delete the descriptor
895  */
896 static void xilinx_dma_free_desc_list(struct xilinx_dma_chan *chan,
897 					struct list_head *list)
898 {
899 	struct xilinx_dma_tx_descriptor *desc, *next;
900 
901 	list_for_each_entry_safe(desc, next, list, node) {
902 		list_del(&desc->node);
903 		xilinx_dma_free_tx_descriptor(chan, desc);
904 	}
905 }
906 
907 /**
908  * xilinx_dma_free_descriptors - Free channel descriptors
909  * @chan: Driver specific DMA channel
910  */
911 static void xilinx_dma_free_descriptors(struct xilinx_dma_chan *chan)
912 {
913 	unsigned long flags;
914 
915 	spin_lock_irqsave(&chan->lock, flags);
916 
917 	xilinx_dma_free_desc_list(chan, &chan->pending_list);
918 	xilinx_dma_free_desc_list(chan, &chan->done_list);
919 	xilinx_dma_free_desc_list(chan, &chan->active_list);
920 
921 	spin_unlock_irqrestore(&chan->lock, flags);
922 }
923 
924 /**
925  * xilinx_dma_free_chan_resources - Free channel resources
926  * @dchan: DMA channel
927  */
928 static void xilinx_dma_free_chan_resources(struct dma_chan *dchan)
929 {
930 	struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
931 	unsigned long flags;
932 
933 	dev_dbg(chan->dev, "Free all channel resources.\n");
934 
935 	xilinx_dma_free_descriptors(chan);
936 
937 	if (chan->xdev->dma_config->dmatype == XDMA_TYPE_AXIDMA) {
938 		spin_lock_irqsave(&chan->lock, flags);
939 		INIT_LIST_HEAD(&chan->free_seg_list);
940 		spin_unlock_irqrestore(&chan->lock, flags);
941 
942 		/* Free memory that is allocated for BD */
943 		dma_free_coherent(chan->dev, sizeof(*chan->seg_v) *
944 				  XILINX_DMA_NUM_DESCS, chan->seg_v,
945 				  chan->seg_p);
946 
947 		/* Free Memory that is allocated for cyclic DMA Mode */
948 		dma_free_coherent(chan->dev, sizeof(*chan->cyclic_seg_v),
949 				  chan->cyclic_seg_v, chan->cyclic_seg_p);
950 	}
951 
952 	if (chan->xdev->dma_config->dmatype == XDMA_TYPE_AXIMCDMA) {
953 		spin_lock_irqsave(&chan->lock, flags);
954 		INIT_LIST_HEAD(&chan->free_seg_list);
955 		spin_unlock_irqrestore(&chan->lock, flags);
956 
957 		/* Free memory that is allocated for BD */
958 		dma_free_coherent(chan->dev, sizeof(*chan->seg_mv) *
959 				  XILINX_DMA_NUM_DESCS, chan->seg_mv,
960 				  chan->seg_p);
961 	}
962 
963 	if (chan->xdev->dma_config->dmatype != XDMA_TYPE_AXIDMA &&
964 	    chan->xdev->dma_config->dmatype != XDMA_TYPE_AXIMCDMA) {
965 		dma_pool_destroy(chan->desc_pool);
966 		chan->desc_pool = NULL;
967 	}
968 
969 }
970 
971 /**
972  * xilinx_dma_get_residue - Compute residue for a given descriptor
973  * @chan: Driver specific dma channel
974  * @desc: dma transaction descriptor
975  *
976  * Return: The number of residue bytes for the descriptor.
977  */
978 static u32 xilinx_dma_get_residue(struct xilinx_dma_chan *chan,
979 				  struct xilinx_dma_tx_descriptor *desc)
980 {
981 	struct xilinx_cdma_tx_segment *cdma_seg;
982 	struct xilinx_axidma_tx_segment *axidma_seg;
983 	struct xilinx_aximcdma_tx_segment *aximcdma_seg;
984 	struct xilinx_cdma_desc_hw *cdma_hw;
985 	struct xilinx_axidma_desc_hw *axidma_hw;
986 	struct xilinx_aximcdma_desc_hw *aximcdma_hw;
987 	struct list_head *entry;
988 	u32 residue = 0;
989 
990 	list_for_each(entry, &desc->segments) {
991 		if (chan->xdev->dma_config->dmatype == XDMA_TYPE_CDMA) {
992 			cdma_seg = list_entry(entry,
993 					      struct xilinx_cdma_tx_segment,
994 					      node);
995 			cdma_hw = &cdma_seg->hw;
996 			residue += (cdma_hw->control - cdma_hw->status) &
997 				   chan->xdev->max_buffer_len;
998 		} else if (chan->xdev->dma_config->dmatype ==
999 			   XDMA_TYPE_AXIDMA) {
1000 			axidma_seg = list_entry(entry,
1001 						struct xilinx_axidma_tx_segment,
1002 						node);
1003 			axidma_hw = &axidma_seg->hw;
1004 			residue += (axidma_hw->control - axidma_hw->status) &
1005 				   chan->xdev->max_buffer_len;
1006 		} else {
1007 			aximcdma_seg =
1008 				list_entry(entry,
1009 					   struct xilinx_aximcdma_tx_segment,
1010 					   node);
1011 			aximcdma_hw = &aximcdma_seg->hw;
1012 			residue +=
1013 				(aximcdma_hw->control - aximcdma_hw->status) &
1014 				chan->xdev->max_buffer_len;
1015 		}
1016 	}
1017 
1018 	return residue;
1019 }
1020 
1021 /**
1022  * xilinx_dma_chan_handle_cyclic - Cyclic dma callback
1023  * @chan: Driver specific dma channel
1024  * @desc: dma transaction descriptor
1025  * @flags: flags for spin lock
1026  */
1027 static void xilinx_dma_chan_handle_cyclic(struct xilinx_dma_chan *chan,
1028 					  struct xilinx_dma_tx_descriptor *desc,
1029 					  unsigned long *flags)
1030 {
1031 	struct dmaengine_desc_callback cb;
1032 
1033 	dmaengine_desc_get_callback(&desc->async_tx, &cb);
1034 	if (dmaengine_desc_callback_valid(&cb)) {
1035 		spin_unlock_irqrestore(&chan->lock, *flags);
1036 		dmaengine_desc_callback_invoke(&cb, NULL);
1037 		spin_lock_irqsave(&chan->lock, *flags);
1038 	}
1039 }
1040 
1041 /**
1042  * xilinx_dma_chan_desc_cleanup - Clean channel descriptors
1043  * @chan: Driver specific DMA channel
1044  */
1045 static void xilinx_dma_chan_desc_cleanup(struct xilinx_dma_chan *chan)
1046 {
1047 	struct xilinx_dma_tx_descriptor *desc, *next;
1048 	unsigned long flags;
1049 
1050 	spin_lock_irqsave(&chan->lock, flags);
1051 
1052 	list_for_each_entry_safe(desc, next, &chan->done_list, node) {
1053 		struct dmaengine_result result;
1054 
1055 		if (desc->cyclic) {
1056 			xilinx_dma_chan_handle_cyclic(chan, desc, &flags);
1057 			break;
1058 		}
1059 
1060 		/* Remove from the list of running transactions */
1061 		list_del(&desc->node);
1062 
1063 		if (unlikely(desc->err)) {
1064 			if (chan->direction == DMA_DEV_TO_MEM)
1065 				result.result = DMA_TRANS_READ_FAILED;
1066 			else
1067 				result.result = DMA_TRANS_WRITE_FAILED;
1068 		} else {
1069 			result.result = DMA_TRANS_NOERROR;
1070 		}
1071 
1072 		result.residue = desc->residue;
1073 
1074 		/* Run the link descriptor callback function */
1075 		spin_unlock_irqrestore(&chan->lock, flags);
1076 		dmaengine_desc_get_callback_invoke(&desc->async_tx, &result);
1077 		spin_lock_irqsave(&chan->lock, flags);
1078 
1079 		/* Run any dependencies, then free the descriptor */
1080 		dma_run_dependencies(&desc->async_tx);
1081 		xilinx_dma_free_tx_descriptor(chan, desc);
1082 
1083 		/*
1084 		 * While we ran a callback the user called a terminate function,
1085 		 * which takes care of cleaning up any remaining descriptors
1086 		 */
1087 		if (chan->terminating)
1088 			break;
1089 	}
1090 
1091 	spin_unlock_irqrestore(&chan->lock, flags);
1092 }
1093 
1094 /**
1095  * xilinx_dma_do_tasklet - Schedule completion tasklet
1096  * @t: Pointer to the Xilinx DMA channel structure
1097  */
1098 static void xilinx_dma_do_tasklet(struct tasklet_struct *t)
1099 {
1100 	struct xilinx_dma_chan *chan = from_tasklet(chan, t, tasklet);
1101 
1102 	xilinx_dma_chan_desc_cleanup(chan);
1103 }
1104 
1105 /**
1106  * xilinx_dma_alloc_chan_resources - Allocate channel resources
1107  * @dchan: DMA channel
1108  *
1109  * Return: '0' on success and failure value on error
1110  */
1111 static int xilinx_dma_alloc_chan_resources(struct dma_chan *dchan)
1112 {
1113 	struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
1114 	int i;
1115 
1116 	/* Has this channel already been allocated? */
1117 	if (chan->desc_pool)
1118 		return 0;
1119 
1120 	/*
1121 	 * We need the descriptor to be aligned to 64bytes
1122 	 * for meeting Xilinx VDMA specification requirement.
1123 	 */
1124 	if (chan->xdev->dma_config->dmatype == XDMA_TYPE_AXIDMA) {
1125 		/* Allocate the buffer descriptors. */
1126 		chan->seg_v = dma_alloc_coherent(chan->dev,
1127 						 sizeof(*chan->seg_v) * XILINX_DMA_NUM_DESCS,
1128 						 &chan->seg_p, GFP_KERNEL);
1129 		if (!chan->seg_v) {
1130 			dev_err(chan->dev,
1131 				"unable to allocate channel %d descriptors\n",
1132 				chan->id);
1133 			return -ENOMEM;
1134 		}
1135 		/*
1136 		 * For cyclic DMA mode we need to program the tail Descriptor
1137 		 * register with a value which is not a part of the BD chain
1138 		 * so allocating a desc segment during channel allocation for
1139 		 * programming tail descriptor.
1140 		 */
1141 		chan->cyclic_seg_v = dma_alloc_coherent(chan->dev,
1142 							sizeof(*chan->cyclic_seg_v),
1143 							&chan->cyclic_seg_p,
1144 							GFP_KERNEL);
1145 		if (!chan->cyclic_seg_v) {
1146 			dev_err(chan->dev,
1147 				"unable to allocate desc segment for cyclic DMA\n");
1148 			dma_free_coherent(chan->dev, sizeof(*chan->seg_v) *
1149 				XILINX_DMA_NUM_DESCS, chan->seg_v,
1150 				chan->seg_p);
1151 			return -ENOMEM;
1152 		}
1153 		chan->cyclic_seg_v->phys = chan->cyclic_seg_p;
1154 
1155 		for (i = 0; i < XILINX_DMA_NUM_DESCS; i++) {
1156 			chan->seg_v[i].hw.next_desc =
1157 			lower_32_bits(chan->seg_p + sizeof(*chan->seg_v) *
1158 				((i + 1) % XILINX_DMA_NUM_DESCS));
1159 			chan->seg_v[i].hw.next_desc_msb =
1160 			upper_32_bits(chan->seg_p + sizeof(*chan->seg_v) *
1161 				((i + 1) % XILINX_DMA_NUM_DESCS));
1162 			chan->seg_v[i].phys = chan->seg_p +
1163 				sizeof(*chan->seg_v) * i;
1164 			list_add_tail(&chan->seg_v[i].node,
1165 				      &chan->free_seg_list);
1166 		}
1167 	} else if (chan->xdev->dma_config->dmatype == XDMA_TYPE_AXIMCDMA) {
1168 		/* Allocate the buffer descriptors. */
1169 		chan->seg_mv = dma_alloc_coherent(chan->dev,
1170 						  sizeof(*chan->seg_mv) *
1171 						  XILINX_DMA_NUM_DESCS,
1172 						  &chan->seg_p, GFP_KERNEL);
1173 		if (!chan->seg_mv) {
1174 			dev_err(chan->dev,
1175 				"unable to allocate channel %d descriptors\n",
1176 				chan->id);
1177 			return -ENOMEM;
1178 		}
1179 		for (i = 0; i < XILINX_DMA_NUM_DESCS; i++) {
1180 			chan->seg_mv[i].hw.next_desc =
1181 			lower_32_bits(chan->seg_p + sizeof(*chan->seg_mv) *
1182 				((i + 1) % XILINX_DMA_NUM_DESCS));
1183 			chan->seg_mv[i].hw.next_desc_msb =
1184 			upper_32_bits(chan->seg_p + sizeof(*chan->seg_mv) *
1185 				((i + 1) % XILINX_DMA_NUM_DESCS));
1186 			chan->seg_mv[i].phys = chan->seg_p +
1187 				sizeof(*chan->seg_mv) * i;
1188 			list_add_tail(&chan->seg_mv[i].node,
1189 				      &chan->free_seg_list);
1190 		}
1191 	} else if (chan->xdev->dma_config->dmatype == XDMA_TYPE_CDMA) {
1192 		chan->desc_pool = dma_pool_create("xilinx_cdma_desc_pool",
1193 				   chan->dev,
1194 				   sizeof(struct xilinx_cdma_tx_segment),
1195 				   __alignof__(struct xilinx_cdma_tx_segment),
1196 				   0);
1197 	} else {
1198 		chan->desc_pool = dma_pool_create("xilinx_vdma_desc_pool",
1199 				     chan->dev,
1200 				     sizeof(struct xilinx_vdma_tx_segment),
1201 				     __alignof__(struct xilinx_vdma_tx_segment),
1202 				     0);
1203 	}
1204 
1205 	if (!chan->desc_pool &&
1206 	    ((chan->xdev->dma_config->dmatype != XDMA_TYPE_AXIDMA) &&
1207 		chan->xdev->dma_config->dmatype != XDMA_TYPE_AXIMCDMA)) {
1208 		dev_err(chan->dev,
1209 			"unable to allocate channel %d descriptor pool\n",
1210 			chan->id);
1211 		return -ENOMEM;
1212 	}
1213 
1214 	dma_cookie_init(dchan);
1215 
1216 	if (chan->xdev->dma_config->dmatype == XDMA_TYPE_AXIDMA) {
1217 		/* For AXI DMA resetting once channel will reset the
1218 		 * other channel as well so enable the interrupts here.
1219 		 */
1220 		dma_ctrl_set(chan, XILINX_DMA_REG_DMACR,
1221 			      XILINX_DMA_DMAXR_ALL_IRQ_MASK);
1222 	}
1223 
1224 	if ((chan->xdev->dma_config->dmatype == XDMA_TYPE_CDMA) && chan->has_sg)
1225 		dma_ctrl_set(chan, XILINX_DMA_REG_DMACR,
1226 			     XILINX_CDMA_CR_SGMODE);
1227 
1228 	return 0;
1229 }
1230 
1231 /**
1232  * xilinx_dma_calc_copysize - Calculate the amount of data to copy
1233  * @chan: Driver specific DMA channel
1234  * @size: Total data that needs to be copied
1235  * @done: Amount of data that has been already copied
1236  *
1237  * Return: Amount of data that has to be copied
1238  */
1239 static int xilinx_dma_calc_copysize(struct xilinx_dma_chan *chan,
1240 				    int size, int done)
1241 {
1242 	size_t copy;
1243 
1244 	copy = min_t(size_t, size - done,
1245 		     chan->xdev->max_buffer_len);
1246 
1247 	if ((copy + done < size) &&
1248 	    chan->xdev->common.copy_align) {
1249 		/*
1250 		 * If this is not the last descriptor, make sure
1251 		 * the next one will be properly aligned
1252 		 */
1253 		copy = rounddown(copy,
1254 				 (1 << chan->xdev->common.copy_align));
1255 	}
1256 	return copy;
1257 }
1258 
1259 /**
1260  * xilinx_dma_tx_status - Get DMA transaction status
1261  * @dchan: DMA channel
1262  * @cookie: Transaction identifier
1263  * @txstate: Transaction state
1264  *
1265  * Return: DMA transaction status
1266  */
1267 static enum dma_status xilinx_dma_tx_status(struct dma_chan *dchan,
1268 					dma_cookie_t cookie,
1269 					struct dma_tx_state *txstate)
1270 {
1271 	struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
1272 	struct xilinx_dma_tx_descriptor *desc;
1273 	enum dma_status ret;
1274 	unsigned long flags;
1275 	u32 residue = 0;
1276 
1277 	ret = dma_cookie_status(dchan, cookie, txstate);
1278 	if (ret == DMA_COMPLETE || !txstate)
1279 		return ret;
1280 
1281 	spin_lock_irqsave(&chan->lock, flags);
1282 	if (!list_empty(&chan->active_list)) {
1283 		desc = list_last_entry(&chan->active_list,
1284 				       struct xilinx_dma_tx_descriptor, node);
1285 		/*
1286 		 * VDMA and simple mode do not support residue reporting, so the
1287 		 * residue field will always be 0.
1288 		 */
1289 		if (chan->has_sg && chan->xdev->dma_config->dmatype != XDMA_TYPE_VDMA)
1290 			residue = xilinx_dma_get_residue(chan, desc);
1291 	}
1292 	spin_unlock_irqrestore(&chan->lock, flags);
1293 
1294 	dma_set_residue(txstate, residue);
1295 
1296 	return ret;
1297 }
1298 
1299 /**
1300  * xilinx_dma_stop_transfer - Halt DMA channel
1301  * @chan: Driver specific DMA channel
1302  *
1303  * Return: '0' on success and failure value on error
1304  */
1305 static int xilinx_dma_stop_transfer(struct xilinx_dma_chan *chan)
1306 {
1307 	u32 val;
1308 
1309 	dma_ctrl_clr(chan, XILINX_DMA_REG_DMACR, XILINX_DMA_DMACR_RUNSTOP);
1310 
1311 	/* Wait for the hardware to halt */
1312 	return xilinx_dma_poll_timeout(chan, XILINX_DMA_REG_DMASR, val,
1313 				       val & XILINX_DMA_DMASR_HALTED, 0,
1314 				       XILINX_DMA_LOOP_COUNT);
1315 }
1316 
1317 /**
1318  * xilinx_cdma_stop_transfer - Wait for the current transfer to complete
1319  * @chan: Driver specific DMA channel
1320  *
1321  * Return: '0' on success and failure value on error
1322  */
1323 static int xilinx_cdma_stop_transfer(struct xilinx_dma_chan *chan)
1324 {
1325 	u32 val;
1326 
1327 	return xilinx_dma_poll_timeout(chan, XILINX_DMA_REG_DMASR, val,
1328 				       val & XILINX_DMA_DMASR_IDLE, 0,
1329 				       XILINX_DMA_LOOP_COUNT);
1330 }
1331 
1332 /**
1333  * xilinx_dma_start - Start DMA channel
1334  * @chan: Driver specific DMA channel
1335  */
1336 static void xilinx_dma_start(struct xilinx_dma_chan *chan)
1337 {
1338 	int err;
1339 	u32 val;
1340 
1341 	dma_ctrl_set(chan, XILINX_DMA_REG_DMACR, XILINX_DMA_DMACR_RUNSTOP);
1342 
1343 	/* Wait for the hardware to start */
1344 	err = xilinx_dma_poll_timeout(chan, XILINX_DMA_REG_DMASR, val,
1345 				      !(val & XILINX_DMA_DMASR_HALTED), 0,
1346 				      XILINX_DMA_LOOP_COUNT);
1347 
1348 	if (err) {
1349 		dev_err(chan->dev, "Cannot start channel %p: %x\n",
1350 			chan, dma_ctrl_read(chan, XILINX_DMA_REG_DMASR));
1351 
1352 		chan->err = true;
1353 	}
1354 }
1355 
1356 /**
1357  * xilinx_vdma_start_transfer - Starts VDMA transfer
1358  * @chan: Driver specific channel struct pointer
1359  */
1360 static void xilinx_vdma_start_transfer(struct xilinx_dma_chan *chan)
1361 {
1362 	struct xilinx_vdma_config *config = &chan->config;
1363 	struct xilinx_dma_tx_descriptor *desc;
1364 	u32 reg, j;
1365 	struct xilinx_vdma_tx_segment *segment, *last = NULL;
1366 	int i = 0;
1367 
1368 	/* This function was invoked with lock held */
1369 	if (chan->err)
1370 		return;
1371 
1372 	if (!chan->idle)
1373 		return;
1374 
1375 	if (list_empty(&chan->pending_list))
1376 		return;
1377 
1378 	desc = list_first_entry(&chan->pending_list,
1379 				struct xilinx_dma_tx_descriptor, node);
1380 
1381 	/* Configure the hardware using info in the config structure */
1382 	if (chan->has_vflip) {
1383 		reg = dma_read(chan, XILINX_VDMA_REG_ENABLE_VERTICAL_FLIP);
1384 		reg &= ~XILINX_VDMA_ENABLE_VERTICAL_FLIP;
1385 		reg |= config->vflip_en;
1386 		dma_write(chan, XILINX_VDMA_REG_ENABLE_VERTICAL_FLIP,
1387 			  reg);
1388 	}
1389 
1390 	reg = dma_ctrl_read(chan, XILINX_DMA_REG_DMACR);
1391 
1392 	if (config->frm_cnt_en)
1393 		reg |= XILINX_DMA_DMACR_FRAMECNT_EN;
1394 	else
1395 		reg &= ~XILINX_DMA_DMACR_FRAMECNT_EN;
1396 
1397 	/* If not parking, enable circular mode */
1398 	if (config->park)
1399 		reg &= ~XILINX_DMA_DMACR_CIRC_EN;
1400 	else
1401 		reg |= XILINX_DMA_DMACR_CIRC_EN;
1402 
1403 	dma_ctrl_write(chan, XILINX_DMA_REG_DMACR, reg);
1404 
1405 	j = chan->desc_submitcount;
1406 	reg = dma_read(chan, XILINX_DMA_REG_PARK_PTR);
1407 	if (chan->direction == DMA_MEM_TO_DEV) {
1408 		reg &= ~XILINX_DMA_PARK_PTR_RD_REF_MASK;
1409 		reg |= j << XILINX_DMA_PARK_PTR_RD_REF_SHIFT;
1410 	} else {
1411 		reg &= ~XILINX_DMA_PARK_PTR_WR_REF_MASK;
1412 		reg |= j << XILINX_DMA_PARK_PTR_WR_REF_SHIFT;
1413 	}
1414 	dma_write(chan, XILINX_DMA_REG_PARK_PTR, reg);
1415 
1416 	/* Start the hardware */
1417 	xilinx_dma_start(chan);
1418 
1419 	if (chan->err)
1420 		return;
1421 
1422 	/* Start the transfer */
1423 	if (chan->desc_submitcount < chan->num_frms)
1424 		i = chan->desc_submitcount;
1425 
1426 	list_for_each_entry(segment, &desc->segments, node) {
1427 		if (chan->ext_addr)
1428 			vdma_desc_write_64(chan,
1429 				   XILINX_VDMA_REG_START_ADDRESS_64(i++),
1430 				   segment->hw.buf_addr,
1431 				   segment->hw.buf_addr_msb);
1432 		else
1433 			vdma_desc_write(chan,
1434 					XILINX_VDMA_REG_START_ADDRESS(i++),
1435 					segment->hw.buf_addr);
1436 
1437 		last = segment;
1438 	}
1439 
1440 	if (!last)
1441 		return;
1442 
1443 	/* HW expects these parameters to be same for one transaction */
1444 	vdma_desc_write(chan, XILINX_DMA_REG_HSIZE, last->hw.hsize);
1445 	vdma_desc_write(chan, XILINX_DMA_REG_FRMDLY_STRIDE,
1446 			last->hw.stride);
1447 	vdma_desc_write(chan, XILINX_DMA_REG_VSIZE, last->hw.vsize);
1448 
1449 	chan->desc_submitcount++;
1450 	chan->desc_pendingcount--;
1451 	list_move_tail(&desc->node, &chan->active_list);
1452 	if (chan->desc_submitcount == chan->num_frms)
1453 		chan->desc_submitcount = 0;
1454 
1455 	chan->idle = false;
1456 }
1457 
1458 /**
1459  * xilinx_cdma_start_transfer - Starts cdma transfer
1460  * @chan: Driver specific channel struct pointer
1461  */
1462 static void xilinx_cdma_start_transfer(struct xilinx_dma_chan *chan)
1463 {
1464 	struct xilinx_dma_tx_descriptor *head_desc, *tail_desc;
1465 	struct xilinx_cdma_tx_segment *tail_segment;
1466 	u32 ctrl_reg = dma_read(chan, XILINX_DMA_REG_DMACR);
1467 
1468 	if (chan->err)
1469 		return;
1470 
1471 	if (!chan->idle)
1472 		return;
1473 
1474 	if (list_empty(&chan->pending_list))
1475 		return;
1476 
1477 	head_desc = list_first_entry(&chan->pending_list,
1478 				     struct xilinx_dma_tx_descriptor, node);
1479 	tail_desc = list_last_entry(&chan->pending_list,
1480 				    struct xilinx_dma_tx_descriptor, node);
1481 	tail_segment = list_last_entry(&tail_desc->segments,
1482 				       struct xilinx_cdma_tx_segment, node);
1483 
1484 	if (chan->desc_pendingcount <= XILINX_DMA_COALESCE_MAX) {
1485 		ctrl_reg &= ~XILINX_DMA_CR_COALESCE_MAX;
1486 		ctrl_reg |= chan->desc_pendingcount <<
1487 				XILINX_DMA_CR_COALESCE_SHIFT;
1488 		dma_ctrl_write(chan, XILINX_DMA_REG_DMACR, ctrl_reg);
1489 	}
1490 
1491 	if (chan->has_sg) {
1492 		dma_ctrl_clr(chan, XILINX_DMA_REG_DMACR,
1493 			     XILINX_CDMA_CR_SGMODE);
1494 
1495 		dma_ctrl_set(chan, XILINX_DMA_REG_DMACR,
1496 			     XILINX_CDMA_CR_SGMODE);
1497 
1498 		xilinx_write(chan, XILINX_DMA_REG_CURDESC,
1499 			     head_desc->async_tx.phys);
1500 
1501 		/* Update tail ptr register which will start the transfer */
1502 		xilinx_write(chan, XILINX_DMA_REG_TAILDESC,
1503 			     tail_segment->phys);
1504 	} else {
1505 		/* In simple mode */
1506 		struct xilinx_cdma_tx_segment *segment;
1507 		struct xilinx_cdma_desc_hw *hw;
1508 
1509 		segment = list_first_entry(&head_desc->segments,
1510 					   struct xilinx_cdma_tx_segment,
1511 					   node);
1512 
1513 		hw = &segment->hw;
1514 
1515 		xilinx_write(chan, XILINX_CDMA_REG_SRCADDR,
1516 			     xilinx_prep_dma_addr_t(hw->src_addr));
1517 		xilinx_write(chan, XILINX_CDMA_REG_DSTADDR,
1518 			     xilinx_prep_dma_addr_t(hw->dest_addr));
1519 
1520 		/* Start the transfer */
1521 		dma_ctrl_write(chan, XILINX_DMA_REG_BTT,
1522 				hw->control & chan->xdev->max_buffer_len);
1523 	}
1524 
1525 	list_splice_tail_init(&chan->pending_list, &chan->active_list);
1526 	chan->desc_pendingcount = 0;
1527 	chan->idle = false;
1528 }
1529 
1530 /**
1531  * xilinx_dma_start_transfer - Starts DMA transfer
1532  * @chan: Driver specific channel struct pointer
1533  */
1534 static void xilinx_dma_start_transfer(struct xilinx_dma_chan *chan)
1535 {
1536 	struct xilinx_dma_tx_descriptor *head_desc, *tail_desc;
1537 	struct xilinx_axidma_tx_segment *tail_segment;
1538 	u32 reg;
1539 
1540 	if (chan->err)
1541 		return;
1542 
1543 	if (list_empty(&chan->pending_list))
1544 		return;
1545 
1546 	if (!chan->idle)
1547 		return;
1548 
1549 	head_desc = list_first_entry(&chan->pending_list,
1550 				     struct xilinx_dma_tx_descriptor, node);
1551 	tail_desc = list_last_entry(&chan->pending_list,
1552 				    struct xilinx_dma_tx_descriptor, node);
1553 	tail_segment = list_last_entry(&tail_desc->segments,
1554 				       struct xilinx_axidma_tx_segment, node);
1555 
1556 	reg = dma_ctrl_read(chan, XILINX_DMA_REG_DMACR);
1557 
1558 	if (chan->desc_pendingcount <= XILINX_DMA_COALESCE_MAX) {
1559 		reg &= ~XILINX_DMA_CR_COALESCE_MAX;
1560 		reg |= chan->desc_pendingcount <<
1561 				  XILINX_DMA_CR_COALESCE_SHIFT;
1562 		dma_ctrl_write(chan, XILINX_DMA_REG_DMACR, reg);
1563 	}
1564 
1565 	if (chan->has_sg)
1566 		xilinx_write(chan, XILINX_DMA_REG_CURDESC,
1567 			     head_desc->async_tx.phys);
1568 	reg  &= ~XILINX_DMA_CR_DELAY_MAX;
1569 	reg  |= chan->irq_delay << XILINX_DMA_CR_DELAY_SHIFT;
1570 	dma_ctrl_write(chan, XILINX_DMA_REG_DMACR, reg);
1571 
1572 	xilinx_dma_start(chan);
1573 
1574 	if (chan->err)
1575 		return;
1576 
1577 	/* Start the transfer */
1578 	if (chan->has_sg) {
1579 		if (chan->cyclic)
1580 			xilinx_write(chan, XILINX_DMA_REG_TAILDESC,
1581 				     chan->cyclic_seg_v->phys);
1582 		else
1583 			xilinx_write(chan, XILINX_DMA_REG_TAILDESC,
1584 				     tail_segment->phys);
1585 	} else {
1586 		struct xilinx_axidma_tx_segment *segment;
1587 		struct xilinx_axidma_desc_hw *hw;
1588 
1589 		segment = list_first_entry(&head_desc->segments,
1590 					   struct xilinx_axidma_tx_segment,
1591 					   node);
1592 		hw = &segment->hw;
1593 
1594 		xilinx_write(chan, XILINX_DMA_REG_SRCDSTADDR,
1595 			     xilinx_prep_dma_addr_t(hw->buf_addr));
1596 
1597 		/* Start the transfer */
1598 		dma_ctrl_write(chan, XILINX_DMA_REG_BTT,
1599 			       hw->control & chan->xdev->max_buffer_len);
1600 	}
1601 
1602 	list_splice_tail_init(&chan->pending_list, &chan->active_list);
1603 	chan->desc_pendingcount = 0;
1604 	chan->idle = false;
1605 }
1606 
1607 /**
1608  * xilinx_mcdma_start_transfer - Starts MCDMA transfer
1609  * @chan: Driver specific channel struct pointer
1610  */
1611 static void xilinx_mcdma_start_transfer(struct xilinx_dma_chan *chan)
1612 {
1613 	struct xilinx_dma_tx_descriptor *head_desc, *tail_desc;
1614 	struct xilinx_aximcdma_tx_segment *tail_segment;
1615 	u32 reg;
1616 
1617 	/*
1618 	 * lock has been held by calling functions, so we don't need it
1619 	 * to take it here again.
1620 	 */
1621 
1622 	if (chan->err)
1623 		return;
1624 
1625 	if (!chan->idle)
1626 		return;
1627 
1628 	if (list_empty(&chan->pending_list))
1629 		return;
1630 
1631 	head_desc = list_first_entry(&chan->pending_list,
1632 				     struct xilinx_dma_tx_descriptor, node);
1633 	tail_desc = list_last_entry(&chan->pending_list,
1634 				    struct xilinx_dma_tx_descriptor, node);
1635 	tail_segment = list_last_entry(&tail_desc->segments,
1636 				       struct xilinx_aximcdma_tx_segment, node);
1637 
1638 	reg = dma_ctrl_read(chan, XILINX_MCDMA_CHAN_CR_OFFSET(chan->tdest));
1639 
1640 	if (chan->desc_pendingcount <= XILINX_MCDMA_COALESCE_MAX) {
1641 		reg &= ~XILINX_MCDMA_COALESCE_MASK;
1642 		reg |= chan->desc_pendingcount <<
1643 			XILINX_MCDMA_COALESCE_SHIFT;
1644 	}
1645 
1646 	reg |= XILINX_MCDMA_IRQ_ALL_MASK;
1647 	dma_ctrl_write(chan, XILINX_MCDMA_CHAN_CR_OFFSET(chan->tdest), reg);
1648 
1649 	/* Program current descriptor */
1650 	xilinx_write(chan, XILINX_MCDMA_CHAN_CDESC_OFFSET(chan->tdest),
1651 		     head_desc->async_tx.phys);
1652 
1653 	/* Program channel enable register */
1654 	reg = dma_ctrl_read(chan, XILINX_MCDMA_CHEN_OFFSET);
1655 	reg |= BIT(chan->tdest);
1656 	dma_ctrl_write(chan, XILINX_MCDMA_CHEN_OFFSET, reg);
1657 
1658 	/* Start the fetch of BDs for the channel */
1659 	reg = dma_ctrl_read(chan, XILINX_MCDMA_CHAN_CR_OFFSET(chan->tdest));
1660 	reg |= XILINX_MCDMA_CR_RUNSTOP_MASK;
1661 	dma_ctrl_write(chan, XILINX_MCDMA_CHAN_CR_OFFSET(chan->tdest), reg);
1662 
1663 	xilinx_dma_start(chan);
1664 
1665 	if (chan->err)
1666 		return;
1667 
1668 	/* Start the transfer */
1669 	xilinx_write(chan, XILINX_MCDMA_CHAN_TDESC_OFFSET(chan->tdest),
1670 		     tail_segment->phys);
1671 
1672 	list_splice_tail_init(&chan->pending_list, &chan->active_list);
1673 	chan->desc_pendingcount = 0;
1674 	chan->idle = false;
1675 }
1676 
1677 /**
1678  * xilinx_dma_issue_pending - Issue pending transactions
1679  * @dchan: DMA channel
1680  */
1681 static void xilinx_dma_issue_pending(struct dma_chan *dchan)
1682 {
1683 	struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
1684 	unsigned long flags;
1685 
1686 	spin_lock_irqsave(&chan->lock, flags);
1687 	chan->start_transfer(chan);
1688 	spin_unlock_irqrestore(&chan->lock, flags);
1689 }
1690 
1691 /**
1692  * xilinx_dma_device_config - Configure the DMA channel
1693  * @dchan: DMA channel
1694  * @config: channel configuration
1695  *
1696  * Return: 0 always.
1697  */
1698 static int xilinx_dma_device_config(struct dma_chan *dchan,
1699 				    struct dma_slave_config *config)
1700 {
1701 	return 0;
1702 }
1703 
1704 /**
1705  * xilinx_dma_complete_descriptor - Mark the active descriptor as complete
1706  * @chan : xilinx DMA channel
1707  *
1708  * CONTEXT: hardirq
1709  */
1710 static void xilinx_dma_complete_descriptor(struct xilinx_dma_chan *chan)
1711 {
1712 	struct xilinx_dma_tx_descriptor *desc, *next;
1713 
1714 	/* This function was invoked with lock held */
1715 	if (list_empty(&chan->active_list))
1716 		return;
1717 
1718 	list_for_each_entry_safe(desc, next, &chan->active_list, node) {
1719 		if (chan->xdev->dma_config->dmatype == XDMA_TYPE_AXIDMA) {
1720 			struct xilinx_axidma_tx_segment *seg;
1721 
1722 			seg = list_last_entry(&desc->segments,
1723 					      struct xilinx_axidma_tx_segment, node);
1724 			if (!(seg->hw.status & XILINX_DMA_BD_COMP_MASK) && chan->has_sg)
1725 				break;
1726 		}
1727 		if (chan->has_sg && chan->xdev->dma_config->dmatype !=
1728 		    XDMA_TYPE_VDMA)
1729 			desc->residue = xilinx_dma_get_residue(chan, desc);
1730 		else
1731 			desc->residue = 0;
1732 		desc->err = chan->err;
1733 
1734 		list_del(&desc->node);
1735 		if (!desc->cyclic)
1736 			dma_cookie_complete(&desc->async_tx);
1737 		list_add_tail(&desc->node, &chan->done_list);
1738 	}
1739 }
1740 
1741 /**
1742  * xilinx_dma_reset - Reset DMA channel
1743  * @chan: Driver specific DMA channel
1744  *
1745  * Return: '0' on success and failure value on error
1746  */
1747 static int xilinx_dma_reset(struct xilinx_dma_chan *chan)
1748 {
1749 	int err;
1750 	u32 tmp;
1751 
1752 	dma_ctrl_set(chan, XILINX_DMA_REG_DMACR, XILINX_DMA_DMACR_RESET);
1753 
1754 	/* Wait for the hardware to finish reset */
1755 	err = xilinx_dma_poll_timeout(chan, XILINX_DMA_REG_DMACR, tmp,
1756 				      !(tmp & XILINX_DMA_DMACR_RESET), 0,
1757 				      XILINX_DMA_LOOP_COUNT);
1758 
1759 	if (err) {
1760 		dev_err(chan->dev, "reset timeout, cr %x, sr %x\n",
1761 			dma_ctrl_read(chan, XILINX_DMA_REG_DMACR),
1762 			dma_ctrl_read(chan, XILINX_DMA_REG_DMASR));
1763 		return -ETIMEDOUT;
1764 	}
1765 
1766 	chan->err = false;
1767 	chan->idle = true;
1768 	chan->desc_pendingcount = 0;
1769 	chan->desc_submitcount = 0;
1770 
1771 	return err;
1772 }
1773 
1774 /**
1775  * xilinx_dma_chan_reset - Reset DMA channel and enable interrupts
1776  * @chan: Driver specific DMA channel
1777  *
1778  * Return: '0' on success and failure value on error
1779  */
1780 static int xilinx_dma_chan_reset(struct xilinx_dma_chan *chan)
1781 {
1782 	int err;
1783 
1784 	/* Reset VDMA */
1785 	err = xilinx_dma_reset(chan);
1786 	if (err)
1787 		return err;
1788 
1789 	/* Enable interrupts */
1790 	dma_ctrl_set(chan, XILINX_DMA_REG_DMACR,
1791 		      XILINX_DMA_DMAXR_ALL_IRQ_MASK);
1792 
1793 	return 0;
1794 }
1795 
1796 /**
1797  * xilinx_mcdma_irq_handler - MCDMA Interrupt handler
1798  * @irq: IRQ number
1799  * @data: Pointer to the Xilinx MCDMA channel structure
1800  *
1801  * Return: IRQ_HANDLED/IRQ_NONE
1802  */
1803 static irqreturn_t xilinx_mcdma_irq_handler(int irq, void *data)
1804 {
1805 	struct xilinx_dma_chan *chan = data;
1806 	u32 status, ser_offset, chan_sermask, chan_offset = 0, chan_id;
1807 
1808 	if (chan->direction == DMA_DEV_TO_MEM)
1809 		ser_offset = XILINX_MCDMA_RXINT_SER_OFFSET;
1810 	else
1811 		ser_offset = XILINX_MCDMA_TXINT_SER_OFFSET;
1812 
1813 	/* Read the channel id raising the interrupt*/
1814 	chan_sermask = dma_ctrl_read(chan, ser_offset);
1815 	chan_id = ffs(chan_sermask);
1816 
1817 	if (!chan_id)
1818 		return IRQ_NONE;
1819 
1820 	if (chan->direction == DMA_DEV_TO_MEM)
1821 		chan_offset = chan->xdev->dma_config->max_channels / 2;
1822 
1823 	chan_offset = chan_offset + (chan_id - 1);
1824 	chan = chan->xdev->chan[chan_offset];
1825 	/* Read the status and ack the interrupts. */
1826 	status = dma_ctrl_read(chan, XILINX_MCDMA_CHAN_SR_OFFSET(chan->tdest));
1827 	if (!(status & XILINX_MCDMA_IRQ_ALL_MASK))
1828 		return IRQ_NONE;
1829 
1830 	dma_ctrl_write(chan, XILINX_MCDMA_CHAN_SR_OFFSET(chan->tdest),
1831 		       status & XILINX_MCDMA_IRQ_ALL_MASK);
1832 
1833 	if (status & XILINX_MCDMA_IRQ_ERR_MASK) {
1834 		dev_err(chan->dev, "Channel %p has errors %x cdr %x tdr %x\n",
1835 			chan,
1836 			dma_ctrl_read(chan, XILINX_MCDMA_CH_ERR_OFFSET),
1837 			dma_ctrl_read(chan, XILINX_MCDMA_CHAN_CDESC_OFFSET
1838 				      (chan->tdest)),
1839 			dma_ctrl_read(chan, XILINX_MCDMA_CHAN_TDESC_OFFSET
1840 				      (chan->tdest)));
1841 		chan->err = true;
1842 	}
1843 
1844 	if (status & XILINX_MCDMA_IRQ_DELAY_MASK) {
1845 		/*
1846 		 * Device takes too long to do the transfer when user requires
1847 		 * responsiveness.
1848 		 */
1849 		dev_dbg(chan->dev, "Inter-packet latency too long\n");
1850 	}
1851 
1852 	if (status & XILINX_MCDMA_IRQ_IOC_MASK) {
1853 		spin_lock(&chan->lock);
1854 		xilinx_dma_complete_descriptor(chan);
1855 		chan->idle = true;
1856 		chan->start_transfer(chan);
1857 		spin_unlock(&chan->lock);
1858 	}
1859 
1860 	tasklet_hi_schedule(&chan->tasklet);
1861 	return IRQ_HANDLED;
1862 }
1863 
1864 /**
1865  * xilinx_dma_irq_handler - DMA Interrupt handler
1866  * @irq: IRQ number
1867  * @data: Pointer to the Xilinx DMA channel structure
1868  *
1869  * Return: IRQ_HANDLED/IRQ_NONE
1870  */
1871 static irqreturn_t xilinx_dma_irq_handler(int irq, void *data)
1872 {
1873 	struct xilinx_dma_chan *chan = data;
1874 	u32 status;
1875 
1876 	/* Read the status and ack the interrupts. */
1877 	status = dma_ctrl_read(chan, XILINX_DMA_REG_DMASR);
1878 	if (!(status & XILINX_DMA_DMAXR_ALL_IRQ_MASK))
1879 		return IRQ_NONE;
1880 
1881 	dma_ctrl_write(chan, XILINX_DMA_REG_DMASR,
1882 			status & XILINX_DMA_DMAXR_ALL_IRQ_MASK);
1883 
1884 	if (status & XILINX_DMA_DMASR_ERR_IRQ) {
1885 		/*
1886 		 * An error occurred. If C_FLUSH_ON_FSYNC is enabled and the
1887 		 * error is recoverable, ignore it. Otherwise flag the error.
1888 		 *
1889 		 * Only recoverable errors can be cleared in the DMASR register,
1890 		 * make sure not to write to other error bits to 1.
1891 		 */
1892 		u32 errors = status & XILINX_DMA_DMASR_ALL_ERR_MASK;
1893 
1894 		dma_ctrl_write(chan, XILINX_DMA_REG_DMASR,
1895 				errors & XILINX_DMA_DMASR_ERR_RECOVER_MASK);
1896 
1897 		if (!chan->flush_on_fsync ||
1898 		    (errors & ~XILINX_DMA_DMASR_ERR_RECOVER_MASK)) {
1899 			dev_err(chan->dev,
1900 				"Channel %p has errors %x, cdr %x tdr %x\n",
1901 				chan, errors,
1902 				dma_ctrl_read(chan, XILINX_DMA_REG_CURDESC),
1903 				dma_ctrl_read(chan, XILINX_DMA_REG_TAILDESC));
1904 			chan->err = true;
1905 		}
1906 	}
1907 
1908 	if (status & (XILINX_DMA_DMASR_FRM_CNT_IRQ |
1909 		      XILINX_DMA_DMASR_DLY_CNT_IRQ)) {
1910 		spin_lock(&chan->lock);
1911 		xilinx_dma_complete_descriptor(chan);
1912 		chan->idle = true;
1913 		chan->start_transfer(chan);
1914 		spin_unlock(&chan->lock);
1915 	}
1916 
1917 	tasklet_schedule(&chan->tasklet);
1918 	return IRQ_HANDLED;
1919 }
1920 
1921 /**
1922  * append_desc_queue - Queuing descriptor
1923  * @chan: Driver specific dma channel
1924  * @desc: dma transaction descriptor
1925  */
1926 static void append_desc_queue(struct xilinx_dma_chan *chan,
1927 			      struct xilinx_dma_tx_descriptor *desc)
1928 {
1929 	struct xilinx_vdma_tx_segment *tail_segment;
1930 	struct xilinx_dma_tx_descriptor *tail_desc;
1931 	struct xilinx_axidma_tx_segment *axidma_tail_segment;
1932 	struct xilinx_aximcdma_tx_segment *aximcdma_tail_segment;
1933 	struct xilinx_cdma_tx_segment *cdma_tail_segment;
1934 
1935 	if (list_empty(&chan->pending_list))
1936 		goto append;
1937 
1938 	/*
1939 	 * Add the hardware descriptor to the chain of hardware descriptors
1940 	 * that already exists in memory.
1941 	 */
1942 	tail_desc = list_last_entry(&chan->pending_list,
1943 				    struct xilinx_dma_tx_descriptor, node);
1944 	if (chan->xdev->dma_config->dmatype == XDMA_TYPE_VDMA) {
1945 		tail_segment = list_last_entry(&tail_desc->segments,
1946 					       struct xilinx_vdma_tx_segment,
1947 					       node);
1948 		tail_segment->hw.next_desc = (u32)desc->async_tx.phys;
1949 	} else if (chan->xdev->dma_config->dmatype == XDMA_TYPE_CDMA) {
1950 		cdma_tail_segment = list_last_entry(&tail_desc->segments,
1951 						struct xilinx_cdma_tx_segment,
1952 						node);
1953 		cdma_tail_segment->hw.next_desc = (u32)desc->async_tx.phys;
1954 	} else if (chan->xdev->dma_config->dmatype == XDMA_TYPE_AXIDMA) {
1955 		axidma_tail_segment = list_last_entry(&tail_desc->segments,
1956 					       struct xilinx_axidma_tx_segment,
1957 					       node);
1958 		axidma_tail_segment->hw.next_desc = (u32)desc->async_tx.phys;
1959 	} else {
1960 		aximcdma_tail_segment =
1961 			list_last_entry(&tail_desc->segments,
1962 					struct xilinx_aximcdma_tx_segment,
1963 					node);
1964 		aximcdma_tail_segment->hw.next_desc = (u32)desc->async_tx.phys;
1965 	}
1966 
1967 	/*
1968 	 * Add the software descriptor and all children to the list
1969 	 * of pending transactions
1970 	 */
1971 append:
1972 	list_add_tail(&desc->node, &chan->pending_list);
1973 	chan->desc_pendingcount++;
1974 
1975 	if (chan->has_sg && (chan->xdev->dma_config->dmatype == XDMA_TYPE_VDMA)
1976 	    && unlikely(chan->desc_pendingcount > chan->num_frms)) {
1977 		dev_dbg(chan->dev, "desc pendingcount is too high\n");
1978 		chan->desc_pendingcount = chan->num_frms;
1979 	}
1980 }
1981 
1982 /**
1983  * xilinx_dma_tx_submit - Submit DMA transaction
1984  * @tx: Async transaction descriptor
1985  *
1986  * Return: cookie value on success and failure value on error
1987  */
1988 static dma_cookie_t xilinx_dma_tx_submit(struct dma_async_tx_descriptor *tx)
1989 {
1990 	struct xilinx_dma_tx_descriptor *desc = to_dma_tx_descriptor(tx);
1991 	struct xilinx_dma_chan *chan = to_xilinx_chan(tx->chan);
1992 	dma_cookie_t cookie;
1993 	unsigned long flags;
1994 	int err;
1995 
1996 	if (chan->cyclic) {
1997 		xilinx_dma_free_tx_descriptor(chan, desc);
1998 		return -EBUSY;
1999 	}
2000 
2001 	if (chan->err) {
2002 		/*
2003 		 * If reset fails, need to hard reset the system.
2004 		 * Channel is no longer functional
2005 		 */
2006 		err = xilinx_dma_chan_reset(chan);
2007 		if (err < 0)
2008 			return err;
2009 	}
2010 
2011 	spin_lock_irqsave(&chan->lock, flags);
2012 
2013 	cookie = dma_cookie_assign(tx);
2014 
2015 	/* Put this transaction onto the tail of the pending queue */
2016 	append_desc_queue(chan, desc);
2017 
2018 	if (desc->cyclic)
2019 		chan->cyclic = true;
2020 
2021 	chan->terminating = false;
2022 
2023 	spin_unlock_irqrestore(&chan->lock, flags);
2024 
2025 	return cookie;
2026 }
2027 
2028 /**
2029  * xilinx_vdma_dma_prep_interleaved - prepare a descriptor for a
2030  *	DMA_SLAVE transaction
2031  * @dchan: DMA channel
2032  * @xt: Interleaved template pointer
2033  * @flags: transfer ack flags
2034  *
2035  * Return: Async transaction descriptor on success and NULL on failure
2036  */
2037 static struct dma_async_tx_descriptor *
2038 xilinx_vdma_dma_prep_interleaved(struct dma_chan *dchan,
2039 				 struct dma_interleaved_template *xt,
2040 				 unsigned long flags)
2041 {
2042 	struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
2043 	struct xilinx_dma_tx_descriptor *desc;
2044 	struct xilinx_vdma_tx_segment *segment;
2045 	struct xilinx_vdma_desc_hw *hw;
2046 
2047 	if (!is_slave_direction(xt->dir))
2048 		return NULL;
2049 
2050 	if (!xt->numf || !xt->sgl[0].size)
2051 		return NULL;
2052 
2053 	if (xt->frame_size != 1)
2054 		return NULL;
2055 
2056 	/* Allocate a transaction descriptor. */
2057 	desc = xilinx_dma_alloc_tx_descriptor(chan);
2058 	if (!desc)
2059 		return NULL;
2060 
2061 	dma_async_tx_descriptor_init(&desc->async_tx, &chan->common);
2062 	desc->async_tx.tx_submit = xilinx_dma_tx_submit;
2063 	async_tx_ack(&desc->async_tx);
2064 
2065 	/* Allocate the link descriptor from DMA pool */
2066 	segment = xilinx_vdma_alloc_tx_segment(chan);
2067 	if (!segment)
2068 		goto error;
2069 
2070 	/* Fill in the hardware descriptor */
2071 	hw = &segment->hw;
2072 	hw->vsize = xt->numf;
2073 	hw->hsize = xt->sgl[0].size;
2074 	hw->stride = (xt->sgl[0].icg + xt->sgl[0].size) <<
2075 			XILINX_DMA_FRMDLY_STRIDE_STRIDE_SHIFT;
2076 	hw->stride |= chan->config.frm_dly <<
2077 			XILINX_DMA_FRMDLY_STRIDE_FRMDLY_SHIFT;
2078 
2079 	if (xt->dir != DMA_MEM_TO_DEV) {
2080 		if (chan->ext_addr) {
2081 			hw->buf_addr = lower_32_bits(xt->dst_start);
2082 			hw->buf_addr_msb = upper_32_bits(xt->dst_start);
2083 		} else {
2084 			hw->buf_addr = xt->dst_start;
2085 		}
2086 	} else {
2087 		if (chan->ext_addr) {
2088 			hw->buf_addr = lower_32_bits(xt->src_start);
2089 			hw->buf_addr_msb = upper_32_bits(xt->src_start);
2090 		} else {
2091 			hw->buf_addr = xt->src_start;
2092 		}
2093 	}
2094 
2095 	/* Insert the segment into the descriptor segments list. */
2096 	list_add_tail(&segment->node, &desc->segments);
2097 
2098 	/* Link the last hardware descriptor with the first. */
2099 	segment = list_first_entry(&desc->segments,
2100 				   struct xilinx_vdma_tx_segment, node);
2101 	desc->async_tx.phys = segment->phys;
2102 
2103 	return &desc->async_tx;
2104 
2105 error:
2106 	xilinx_dma_free_tx_descriptor(chan, desc);
2107 	return NULL;
2108 }
2109 
2110 /**
2111  * xilinx_cdma_prep_memcpy - prepare descriptors for a memcpy transaction
2112  * @dchan: DMA channel
2113  * @dma_dst: destination address
2114  * @dma_src: source address
2115  * @len: transfer length
2116  * @flags: transfer ack flags
2117  *
2118  * Return: Async transaction descriptor on success and NULL on failure
2119  */
2120 static struct dma_async_tx_descriptor *
2121 xilinx_cdma_prep_memcpy(struct dma_chan *dchan, dma_addr_t dma_dst,
2122 			dma_addr_t dma_src, size_t len, unsigned long flags)
2123 {
2124 	struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
2125 	struct xilinx_dma_tx_descriptor *desc;
2126 	struct xilinx_cdma_tx_segment *segment;
2127 	struct xilinx_cdma_desc_hw *hw;
2128 
2129 	if (!len || len > chan->xdev->max_buffer_len)
2130 		return NULL;
2131 
2132 	desc = xilinx_dma_alloc_tx_descriptor(chan);
2133 	if (!desc)
2134 		return NULL;
2135 
2136 	dma_async_tx_descriptor_init(&desc->async_tx, &chan->common);
2137 	desc->async_tx.tx_submit = xilinx_dma_tx_submit;
2138 
2139 	/* Allocate the link descriptor from DMA pool */
2140 	segment = xilinx_cdma_alloc_tx_segment(chan);
2141 	if (!segment)
2142 		goto error;
2143 
2144 	hw = &segment->hw;
2145 	hw->control = len;
2146 	hw->src_addr = dma_src;
2147 	hw->dest_addr = dma_dst;
2148 	if (chan->ext_addr) {
2149 		hw->src_addr_msb = upper_32_bits(dma_src);
2150 		hw->dest_addr_msb = upper_32_bits(dma_dst);
2151 	}
2152 
2153 	/* Insert the segment into the descriptor segments list. */
2154 	list_add_tail(&segment->node, &desc->segments);
2155 
2156 	desc->async_tx.phys = segment->phys;
2157 	hw->next_desc = segment->phys;
2158 
2159 	return &desc->async_tx;
2160 
2161 error:
2162 	xilinx_dma_free_tx_descriptor(chan, desc);
2163 	return NULL;
2164 }
2165 
2166 /**
2167  * xilinx_dma_prep_slave_sg - prepare descriptors for a DMA_SLAVE transaction
2168  * @dchan: DMA channel
2169  * @sgl: scatterlist to transfer to/from
2170  * @sg_len: number of entries in @scatterlist
2171  * @direction: DMA direction
2172  * @flags: transfer ack flags
2173  * @context: APP words of the descriptor
2174  *
2175  * Return: Async transaction descriptor on success and NULL on failure
2176  */
2177 static struct dma_async_tx_descriptor *xilinx_dma_prep_slave_sg(
2178 	struct dma_chan *dchan, struct scatterlist *sgl, unsigned int sg_len,
2179 	enum dma_transfer_direction direction, unsigned long flags,
2180 	void *context)
2181 {
2182 	struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
2183 	struct xilinx_dma_tx_descriptor *desc;
2184 	struct xilinx_axidma_tx_segment *segment = NULL;
2185 	u32 *app_w = (u32 *)context;
2186 	struct scatterlist *sg;
2187 	size_t copy;
2188 	size_t sg_used;
2189 	unsigned int i;
2190 
2191 	if (!is_slave_direction(direction))
2192 		return NULL;
2193 
2194 	/* Allocate a transaction descriptor. */
2195 	desc = xilinx_dma_alloc_tx_descriptor(chan);
2196 	if (!desc)
2197 		return NULL;
2198 
2199 	dma_async_tx_descriptor_init(&desc->async_tx, &chan->common);
2200 	desc->async_tx.tx_submit = xilinx_dma_tx_submit;
2201 
2202 	/* Build transactions using information in the scatter gather list */
2203 	for_each_sg(sgl, sg, sg_len, i) {
2204 		sg_used = 0;
2205 
2206 		/* Loop until the entire scatterlist entry is used */
2207 		while (sg_used < sg_dma_len(sg)) {
2208 			struct xilinx_axidma_desc_hw *hw;
2209 
2210 			/* Get a free segment */
2211 			segment = xilinx_axidma_alloc_tx_segment(chan);
2212 			if (!segment)
2213 				goto error;
2214 
2215 			/*
2216 			 * Calculate the maximum number of bytes to transfer,
2217 			 * making sure it is less than the hw limit
2218 			 */
2219 			copy = xilinx_dma_calc_copysize(chan, sg_dma_len(sg),
2220 							sg_used);
2221 			hw = &segment->hw;
2222 
2223 			/* Fill in the descriptor */
2224 			xilinx_axidma_buf(chan, hw, sg_dma_address(sg),
2225 					  sg_used, 0);
2226 
2227 			hw->control = copy;
2228 
2229 			if (chan->direction == DMA_MEM_TO_DEV) {
2230 				if (app_w)
2231 					memcpy(hw->app, app_w, sizeof(u32) *
2232 					       XILINX_DMA_NUM_APP_WORDS);
2233 			}
2234 
2235 			sg_used += copy;
2236 
2237 			/*
2238 			 * Insert the segment into the descriptor segments
2239 			 * list.
2240 			 */
2241 			list_add_tail(&segment->node, &desc->segments);
2242 		}
2243 	}
2244 
2245 	segment = list_first_entry(&desc->segments,
2246 				   struct xilinx_axidma_tx_segment, node);
2247 	desc->async_tx.phys = segment->phys;
2248 
2249 	/* For the last DMA_MEM_TO_DEV transfer, set EOP */
2250 	if (chan->direction == DMA_MEM_TO_DEV) {
2251 		segment->hw.control |= XILINX_DMA_BD_SOP;
2252 		segment = list_last_entry(&desc->segments,
2253 					  struct xilinx_axidma_tx_segment,
2254 					  node);
2255 		segment->hw.control |= XILINX_DMA_BD_EOP;
2256 	}
2257 
2258 	if (chan->xdev->has_axistream_connected)
2259 		desc->async_tx.metadata_ops = &xilinx_dma_metadata_ops;
2260 
2261 	return &desc->async_tx;
2262 
2263 error:
2264 	xilinx_dma_free_tx_descriptor(chan, desc);
2265 	return NULL;
2266 }
2267 
2268 /**
2269  * xilinx_dma_prep_dma_cyclic - prepare descriptors for a DMA_SLAVE transaction
2270  * @dchan: DMA channel
2271  * @buf_addr: Physical address of the buffer
2272  * @buf_len: Total length of the cyclic buffers
2273  * @period_len: length of individual cyclic buffer
2274  * @direction: DMA direction
2275  * @flags: transfer ack flags
2276  *
2277  * Return: Async transaction descriptor on success and NULL on failure
2278  */
2279 static struct dma_async_tx_descriptor *xilinx_dma_prep_dma_cyclic(
2280 	struct dma_chan *dchan, dma_addr_t buf_addr, size_t buf_len,
2281 	size_t period_len, enum dma_transfer_direction direction,
2282 	unsigned long flags)
2283 {
2284 	struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
2285 	struct xilinx_dma_tx_descriptor *desc;
2286 	struct xilinx_axidma_tx_segment *segment, *head_segment, *prev = NULL;
2287 	size_t copy, sg_used;
2288 	unsigned int num_periods;
2289 	int i;
2290 	u32 reg;
2291 
2292 	if (!period_len)
2293 		return NULL;
2294 
2295 	num_periods = buf_len / period_len;
2296 
2297 	if (!num_periods)
2298 		return NULL;
2299 
2300 	if (!is_slave_direction(direction))
2301 		return NULL;
2302 
2303 	/* Allocate a transaction descriptor. */
2304 	desc = xilinx_dma_alloc_tx_descriptor(chan);
2305 	if (!desc)
2306 		return NULL;
2307 
2308 	chan->direction = direction;
2309 	dma_async_tx_descriptor_init(&desc->async_tx, &chan->common);
2310 	desc->async_tx.tx_submit = xilinx_dma_tx_submit;
2311 
2312 	for (i = 0; i < num_periods; ++i) {
2313 		sg_used = 0;
2314 
2315 		while (sg_used < period_len) {
2316 			struct xilinx_axidma_desc_hw *hw;
2317 
2318 			/* Get a free segment */
2319 			segment = xilinx_axidma_alloc_tx_segment(chan);
2320 			if (!segment)
2321 				goto error;
2322 
2323 			/*
2324 			 * Calculate the maximum number of bytes to transfer,
2325 			 * making sure it is less than the hw limit
2326 			 */
2327 			copy = xilinx_dma_calc_copysize(chan, period_len,
2328 							sg_used);
2329 			hw = &segment->hw;
2330 			xilinx_axidma_buf(chan, hw, buf_addr, sg_used,
2331 					  period_len * i);
2332 			hw->control = copy;
2333 
2334 			if (prev)
2335 				prev->hw.next_desc = segment->phys;
2336 
2337 			prev = segment;
2338 			sg_used += copy;
2339 
2340 			/*
2341 			 * Insert the segment into the descriptor segments
2342 			 * list.
2343 			 */
2344 			list_add_tail(&segment->node, &desc->segments);
2345 		}
2346 	}
2347 
2348 	head_segment = list_first_entry(&desc->segments,
2349 				   struct xilinx_axidma_tx_segment, node);
2350 	desc->async_tx.phys = head_segment->phys;
2351 
2352 	desc->cyclic = true;
2353 	reg = dma_ctrl_read(chan, XILINX_DMA_REG_DMACR);
2354 	reg |= XILINX_DMA_CR_CYCLIC_BD_EN_MASK;
2355 	dma_ctrl_write(chan, XILINX_DMA_REG_DMACR, reg);
2356 
2357 	segment = list_last_entry(&desc->segments,
2358 				  struct xilinx_axidma_tx_segment,
2359 				  node);
2360 	segment->hw.next_desc = (u32) head_segment->phys;
2361 
2362 	/* For the last DMA_MEM_TO_DEV transfer, set EOP */
2363 	if (direction == DMA_MEM_TO_DEV) {
2364 		head_segment->hw.control |= XILINX_DMA_BD_SOP;
2365 		segment->hw.control |= XILINX_DMA_BD_EOP;
2366 	}
2367 
2368 	return &desc->async_tx;
2369 
2370 error:
2371 	xilinx_dma_free_tx_descriptor(chan, desc);
2372 	return NULL;
2373 }
2374 
2375 /**
2376  * xilinx_mcdma_prep_slave_sg - prepare descriptors for a DMA_SLAVE transaction
2377  * @dchan: DMA channel
2378  * @sgl: scatterlist to transfer to/from
2379  * @sg_len: number of entries in @scatterlist
2380  * @direction: DMA direction
2381  * @flags: transfer ack flags
2382  * @context: APP words of the descriptor
2383  *
2384  * Return: Async transaction descriptor on success and NULL on failure
2385  */
2386 static struct dma_async_tx_descriptor *
2387 xilinx_mcdma_prep_slave_sg(struct dma_chan *dchan, struct scatterlist *sgl,
2388 			   unsigned int sg_len,
2389 			   enum dma_transfer_direction direction,
2390 			   unsigned long flags, void *context)
2391 {
2392 	struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
2393 	struct xilinx_dma_tx_descriptor *desc;
2394 	struct xilinx_aximcdma_tx_segment *segment = NULL;
2395 	u32 *app_w = (u32 *)context;
2396 	struct scatterlist *sg;
2397 	size_t copy;
2398 	size_t sg_used;
2399 	unsigned int i;
2400 
2401 	if (!is_slave_direction(direction))
2402 		return NULL;
2403 
2404 	/* Allocate a transaction descriptor. */
2405 	desc = xilinx_dma_alloc_tx_descriptor(chan);
2406 	if (!desc)
2407 		return NULL;
2408 
2409 	dma_async_tx_descriptor_init(&desc->async_tx, &chan->common);
2410 	desc->async_tx.tx_submit = xilinx_dma_tx_submit;
2411 
2412 	/* Build transactions using information in the scatter gather list */
2413 	for_each_sg(sgl, sg, sg_len, i) {
2414 		sg_used = 0;
2415 
2416 		/* Loop until the entire scatterlist entry is used */
2417 		while (sg_used < sg_dma_len(sg)) {
2418 			struct xilinx_aximcdma_desc_hw *hw;
2419 
2420 			/* Get a free segment */
2421 			segment = xilinx_aximcdma_alloc_tx_segment(chan);
2422 			if (!segment)
2423 				goto error;
2424 
2425 			/*
2426 			 * Calculate the maximum number of bytes to transfer,
2427 			 * making sure it is less than the hw limit
2428 			 */
2429 			copy = min_t(size_t, sg_dma_len(sg) - sg_used,
2430 				     chan->xdev->max_buffer_len);
2431 			hw = &segment->hw;
2432 
2433 			/* Fill in the descriptor */
2434 			xilinx_aximcdma_buf(chan, hw, sg_dma_address(sg),
2435 					    sg_used);
2436 			hw->control = copy;
2437 
2438 			if (chan->direction == DMA_MEM_TO_DEV && app_w) {
2439 				memcpy(hw->app, app_w, sizeof(u32) *
2440 				       XILINX_DMA_NUM_APP_WORDS);
2441 			}
2442 
2443 			sg_used += copy;
2444 			/*
2445 			 * Insert the segment into the descriptor segments
2446 			 * list.
2447 			 */
2448 			list_add_tail(&segment->node, &desc->segments);
2449 		}
2450 	}
2451 
2452 	segment = list_first_entry(&desc->segments,
2453 				   struct xilinx_aximcdma_tx_segment, node);
2454 	desc->async_tx.phys = segment->phys;
2455 
2456 	/* For the last DMA_MEM_TO_DEV transfer, set EOP */
2457 	if (chan->direction == DMA_MEM_TO_DEV) {
2458 		segment->hw.control |= XILINX_MCDMA_BD_SOP;
2459 		segment = list_last_entry(&desc->segments,
2460 					  struct xilinx_aximcdma_tx_segment,
2461 					  node);
2462 		segment->hw.control |= XILINX_MCDMA_BD_EOP;
2463 	}
2464 
2465 	return &desc->async_tx;
2466 
2467 error:
2468 	xilinx_dma_free_tx_descriptor(chan, desc);
2469 
2470 	return NULL;
2471 }
2472 
2473 /**
2474  * xilinx_dma_terminate_all - Halt the channel and free descriptors
2475  * @dchan: Driver specific DMA Channel pointer
2476  *
2477  * Return: '0' always.
2478  */
2479 static int xilinx_dma_terminate_all(struct dma_chan *dchan)
2480 {
2481 	struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
2482 	u32 reg;
2483 	int err;
2484 
2485 	if (!chan->cyclic) {
2486 		err = chan->stop_transfer(chan);
2487 		if (err) {
2488 			dev_err(chan->dev, "Cannot stop channel %p: %x\n",
2489 				chan, dma_ctrl_read(chan,
2490 				XILINX_DMA_REG_DMASR));
2491 			chan->err = true;
2492 		}
2493 	}
2494 
2495 	xilinx_dma_chan_reset(chan);
2496 	/* Remove and free all of the descriptors in the lists */
2497 	chan->terminating = true;
2498 	xilinx_dma_free_descriptors(chan);
2499 	chan->idle = true;
2500 
2501 	if (chan->cyclic) {
2502 		reg = dma_ctrl_read(chan, XILINX_DMA_REG_DMACR);
2503 		reg &= ~XILINX_DMA_CR_CYCLIC_BD_EN_MASK;
2504 		dma_ctrl_write(chan, XILINX_DMA_REG_DMACR, reg);
2505 		chan->cyclic = false;
2506 	}
2507 
2508 	if ((chan->xdev->dma_config->dmatype == XDMA_TYPE_CDMA) && chan->has_sg)
2509 		dma_ctrl_clr(chan, XILINX_DMA_REG_DMACR,
2510 			     XILINX_CDMA_CR_SGMODE);
2511 
2512 	return 0;
2513 }
2514 
2515 static void xilinx_dma_synchronize(struct dma_chan *dchan)
2516 {
2517 	struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
2518 
2519 	tasklet_kill(&chan->tasklet);
2520 }
2521 
2522 /**
2523  * xilinx_vdma_channel_set_config - Configure VDMA channel
2524  * Run-time configuration for Axi VDMA, supports:
2525  * . halt the channel
2526  * . configure interrupt coalescing and inter-packet delay threshold
2527  * . start/stop parking
2528  * . enable genlock
2529  *
2530  * @dchan: DMA channel
2531  * @cfg: VDMA device configuration pointer
2532  *
2533  * Return: '0' on success and failure value on error
2534  */
2535 int xilinx_vdma_channel_set_config(struct dma_chan *dchan,
2536 					struct xilinx_vdma_config *cfg)
2537 {
2538 	struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
2539 	u32 dmacr;
2540 
2541 	if (cfg->reset)
2542 		return xilinx_dma_chan_reset(chan);
2543 
2544 	dmacr = dma_ctrl_read(chan, XILINX_DMA_REG_DMACR);
2545 
2546 	chan->config.frm_dly = cfg->frm_dly;
2547 	chan->config.park = cfg->park;
2548 
2549 	/* genlock settings */
2550 	chan->config.gen_lock = cfg->gen_lock;
2551 	chan->config.master = cfg->master;
2552 
2553 	dmacr &= ~XILINX_DMA_DMACR_GENLOCK_EN;
2554 	if (cfg->gen_lock && chan->genlock) {
2555 		dmacr |= XILINX_DMA_DMACR_GENLOCK_EN;
2556 		dmacr &= ~XILINX_DMA_DMACR_MASTER_MASK;
2557 		dmacr |= cfg->master << XILINX_DMA_DMACR_MASTER_SHIFT;
2558 	}
2559 
2560 	chan->config.frm_cnt_en = cfg->frm_cnt_en;
2561 	chan->config.vflip_en = cfg->vflip_en;
2562 
2563 	if (cfg->park)
2564 		chan->config.park_frm = cfg->park_frm;
2565 	else
2566 		chan->config.park_frm = -1;
2567 
2568 	chan->config.coalesc = cfg->coalesc;
2569 	chan->config.delay = cfg->delay;
2570 
2571 	if (cfg->coalesc <= XILINX_DMA_DMACR_FRAME_COUNT_MAX) {
2572 		dmacr &= ~XILINX_DMA_DMACR_FRAME_COUNT_MASK;
2573 		dmacr |= cfg->coalesc << XILINX_DMA_DMACR_FRAME_COUNT_SHIFT;
2574 		chan->config.coalesc = cfg->coalesc;
2575 	}
2576 
2577 	if (cfg->delay <= XILINX_DMA_DMACR_DELAY_MAX) {
2578 		dmacr &= ~XILINX_DMA_DMACR_DELAY_MASK;
2579 		dmacr |= cfg->delay << XILINX_DMA_DMACR_DELAY_SHIFT;
2580 		chan->config.delay = cfg->delay;
2581 	}
2582 
2583 	/* FSync Source selection */
2584 	dmacr &= ~XILINX_DMA_DMACR_FSYNCSRC_MASK;
2585 	dmacr |= cfg->ext_fsync << XILINX_DMA_DMACR_FSYNCSRC_SHIFT;
2586 
2587 	dma_ctrl_write(chan, XILINX_DMA_REG_DMACR, dmacr);
2588 
2589 	return 0;
2590 }
2591 EXPORT_SYMBOL(xilinx_vdma_channel_set_config);
2592 
2593 /* -----------------------------------------------------------------------------
2594  * Probe and remove
2595  */
2596 
2597 /**
2598  * xilinx_dma_chan_remove - Per Channel remove function
2599  * @chan: Driver specific DMA channel
2600  */
2601 static void xilinx_dma_chan_remove(struct xilinx_dma_chan *chan)
2602 {
2603 	/* Disable all interrupts */
2604 	dma_ctrl_clr(chan, XILINX_DMA_REG_DMACR,
2605 		      XILINX_DMA_DMAXR_ALL_IRQ_MASK);
2606 
2607 	if (chan->irq > 0)
2608 		free_irq(chan->irq, chan);
2609 
2610 	tasklet_kill(&chan->tasklet);
2611 
2612 	list_del(&chan->common.device_node);
2613 }
2614 
2615 static int axidma_clk_init(struct platform_device *pdev, struct clk **axi_clk,
2616 			    struct clk **tx_clk, struct clk **rx_clk,
2617 			    struct clk **sg_clk, struct clk **tmp_clk)
2618 {
2619 	int err;
2620 
2621 	*tmp_clk = NULL;
2622 
2623 	*axi_clk = devm_clk_get(&pdev->dev, "s_axi_lite_aclk");
2624 	if (IS_ERR(*axi_clk))
2625 		return dev_err_probe(&pdev->dev, PTR_ERR(*axi_clk), "failed to get axi_aclk\n");
2626 
2627 	*tx_clk = devm_clk_get(&pdev->dev, "m_axi_mm2s_aclk");
2628 	if (IS_ERR(*tx_clk))
2629 		*tx_clk = NULL;
2630 
2631 	*rx_clk = devm_clk_get(&pdev->dev, "m_axi_s2mm_aclk");
2632 	if (IS_ERR(*rx_clk))
2633 		*rx_clk = NULL;
2634 
2635 	*sg_clk = devm_clk_get(&pdev->dev, "m_axi_sg_aclk");
2636 	if (IS_ERR(*sg_clk))
2637 		*sg_clk = NULL;
2638 
2639 	err = clk_prepare_enable(*axi_clk);
2640 	if (err) {
2641 		dev_err(&pdev->dev, "failed to enable axi_clk (%d)\n", err);
2642 		return err;
2643 	}
2644 
2645 	err = clk_prepare_enable(*tx_clk);
2646 	if (err) {
2647 		dev_err(&pdev->dev, "failed to enable tx_clk (%d)\n", err);
2648 		goto err_disable_axiclk;
2649 	}
2650 
2651 	err = clk_prepare_enable(*rx_clk);
2652 	if (err) {
2653 		dev_err(&pdev->dev, "failed to enable rx_clk (%d)\n", err);
2654 		goto err_disable_txclk;
2655 	}
2656 
2657 	err = clk_prepare_enable(*sg_clk);
2658 	if (err) {
2659 		dev_err(&pdev->dev, "failed to enable sg_clk (%d)\n", err);
2660 		goto err_disable_rxclk;
2661 	}
2662 
2663 	return 0;
2664 
2665 err_disable_rxclk:
2666 	clk_disable_unprepare(*rx_clk);
2667 err_disable_txclk:
2668 	clk_disable_unprepare(*tx_clk);
2669 err_disable_axiclk:
2670 	clk_disable_unprepare(*axi_clk);
2671 
2672 	return err;
2673 }
2674 
2675 static int axicdma_clk_init(struct platform_device *pdev, struct clk **axi_clk,
2676 			    struct clk **dev_clk, struct clk **tmp_clk,
2677 			    struct clk **tmp1_clk, struct clk **tmp2_clk)
2678 {
2679 	int err;
2680 
2681 	*tmp_clk = NULL;
2682 	*tmp1_clk = NULL;
2683 	*tmp2_clk = NULL;
2684 
2685 	*axi_clk = devm_clk_get(&pdev->dev, "s_axi_lite_aclk");
2686 	if (IS_ERR(*axi_clk))
2687 		return dev_err_probe(&pdev->dev, PTR_ERR(*axi_clk), "failed to get axi_aclk\n");
2688 
2689 	*dev_clk = devm_clk_get(&pdev->dev, "m_axi_aclk");
2690 	if (IS_ERR(*dev_clk))
2691 		return dev_err_probe(&pdev->dev, PTR_ERR(*dev_clk), "failed to get dev_clk\n");
2692 
2693 	err = clk_prepare_enable(*axi_clk);
2694 	if (err) {
2695 		dev_err(&pdev->dev, "failed to enable axi_clk (%d)\n", err);
2696 		return err;
2697 	}
2698 
2699 	err = clk_prepare_enable(*dev_clk);
2700 	if (err) {
2701 		dev_err(&pdev->dev, "failed to enable dev_clk (%d)\n", err);
2702 		goto err_disable_axiclk;
2703 	}
2704 
2705 	return 0;
2706 
2707 err_disable_axiclk:
2708 	clk_disable_unprepare(*axi_clk);
2709 
2710 	return err;
2711 }
2712 
2713 static int axivdma_clk_init(struct platform_device *pdev, struct clk **axi_clk,
2714 			    struct clk **tx_clk, struct clk **txs_clk,
2715 			    struct clk **rx_clk, struct clk **rxs_clk)
2716 {
2717 	int err;
2718 
2719 	*axi_clk = devm_clk_get(&pdev->dev, "s_axi_lite_aclk");
2720 	if (IS_ERR(*axi_clk))
2721 		return dev_err_probe(&pdev->dev, PTR_ERR(*axi_clk), "failed to get axi_aclk\n");
2722 
2723 	*tx_clk = devm_clk_get(&pdev->dev, "m_axi_mm2s_aclk");
2724 	if (IS_ERR(*tx_clk))
2725 		*tx_clk = NULL;
2726 
2727 	*txs_clk = devm_clk_get(&pdev->dev, "m_axis_mm2s_aclk");
2728 	if (IS_ERR(*txs_clk))
2729 		*txs_clk = NULL;
2730 
2731 	*rx_clk = devm_clk_get(&pdev->dev, "m_axi_s2mm_aclk");
2732 	if (IS_ERR(*rx_clk))
2733 		*rx_clk = NULL;
2734 
2735 	*rxs_clk = devm_clk_get(&pdev->dev, "s_axis_s2mm_aclk");
2736 	if (IS_ERR(*rxs_clk))
2737 		*rxs_clk = NULL;
2738 
2739 	err = clk_prepare_enable(*axi_clk);
2740 	if (err) {
2741 		dev_err(&pdev->dev, "failed to enable axi_clk (%d)\n",
2742 			err);
2743 		return err;
2744 	}
2745 
2746 	err = clk_prepare_enable(*tx_clk);
2747 	if (err) {
2748 		dev_err(&pdev->dev, "failed to enable tx_clk (%d)\n", err);
2749 		goto err_disable_axiclk;
2750 	}
2751 
2752 	err = clk_prepare_enable(*txs_clk);
2753 	if (err) {
2754 		dev_err(&pdev->dev, "failed to enable txs_clk (%d)\n", err);
2755 		goto err_disable_txclk;
2756 	}
2757 
2758 	err = clk_prepare_enable(*rx_clk);
2759 	if (err) {
2760 		dev_err(&pdev->dev, "failed to enable rx_clk (%d)\n", err);
2761 		goto err_disable_txsclk;
2762 	}
2763 
2764 	err = clk_prepare_enable(*rxs_clk);
2765 	if (err) {
2766 		dev_err(&pdev->dev, "failed to enable rxs_clk (%d)\n", err);
2767 		goto err_disable_rxclk;
2768 	}
2769 
2770 	return 0;
2771 
2772 err_disable_rxclk:
2773 	clk_disable_unprepare(*rx_clk);
2774 err_disable_txsclk:
2775 	clk_disable_unprepare(*txs_clk);
2776 err_disable_txclk:
2777 	clk_disable_unprepare(*tx_clk);
2778 err_disable_axiclk:
2779 	clk_disable_unprepare(*axi_clk);
2780 
2781 	return err;
2782 }
2783 
2784 static void xdma_disable_allclks(struct xilinx_dma_device *xdev)
2785 {
2786 	clk_disable_unprepare(xdev->rxs_clk);
2787 	clk_disable_unprepare(xdev->rx_clk);
2788 	clk_disable_unprepare(xdev->txs_clk);
2789 	clk_disable_unprepare(xdev->tx_clk);
2790 	clk_disable_unprepare(xdev->axi_clk);
2791 }
2792 
2793 /**
2794  * xilinx_dma_chan_probe - Per Channel Probing
2795  * It get channel features from the device tree entry and
2796  * initialize special channel handling routines
2797  *
2798  * @xdev: Driver specific device structure
2799  * @node: Device node
2800  *
2801  * Return: '0' on success and failure value on error
2802  */
2803 static int xilinx_dma_chan_probe(struct xilinx_dma_device *xdev,
2804 				  struct device_node *node)
2805 {
2806 	struct xilinx_dma_chan *chan;
2807 	bool has_dre = false;
2808 	u32 value, width;
2809 	int err;
2810 
2811 	/* Allocate and initialize the channel structure */
2812 	chan = devm_kzalloc(xdev->dev, sizeof(*chan), GFP_KERNEL);
2813 	if (!chan)
2814 		return -ENOMEM;
2815 
2816 	chan->dev = xdev->dev;
2817 	chan->xdev = xdev;
2818 	chan->desc_pendingcount = 0x0;
2819 	chan->ext_addr = xdev->ext_addr;
2820 	/* This variable ensures that descriptors are not
2821 	 * Submitted when dma engine is in progress. This variable is
2822 	 * Added to avoid polling for a bit in the status register to
2823 	 * Know dma state in the driver hot path.
2824 	 */
2825 	chan->idle = true;
2826 
2827 	spin_lock_init(&chan->lock);
2828 	INIT_LIST_HEAD(&chan->pending_list);
2829 	INIT_LIST_HEAD(&chan->done_list);
2830 	INIT_LIST_HEAD(&chan->active_list);
2831 	INIT_LIST_HEAD(&chan->free_seg_list);
2832 
2833 	/* Retrieve the channel properties from the device tree */
2834 	has_dre = of_property_read_bool(node, "xlnx,include-dre");
2835 
2836 	of_property_read_u8(node, "xlnx,irq-delay", &chan->irq_delay);
2837 
2838 	chan->genlock = of_property_read_bool(node, "xlnx,genlock-mode");
2839 
2840 	err = of_property_read_u32(node, "xlnx,datawidth", &value);
2841 	if (err) {
2842 		dev_err(xdev->dev, "missing xlnx,datawidth property\n");
2843 		return err;
2844 	}
2845 	width = value >> 3; /* Convert bits to bytes */
2846 
2847 	/* If data width is greater than 8 bytes, DRE is not in hw */
2848 	if (width > 8)
2849 		has_dre = false;
2850 
2851 	if (!has_dre)
2852 		xdev->common.copy_align = (enum dmaengine_alignment)fls(width - 1);
2853 
2854 	if (of_device_is_compatible(node, "xlnx,axi-vdma-mm2s-channel") ||
2855 	    of_device_is_compatible(node, "xlnx,axi-dma-mm2s-channel") ||
2856 	    of_device_is_compatible(node, "xlnx,axi-cdma-channel")) {
2857 		chan->direction = DMA_MEM_TO_DEV;
2858 		chan->id = xdev->mm2s_chan_id++;
2859 		chan->tdest = chan->id;
2860 
2861 		chan->ctrl_offset = XILINX_DMA_MM2S_CTRL_OFFSET;
2862 		if (xdev->dma_config->dmatype == XDMA_TYPE_VDMA) {
2863 			chan->desc_offset = XILINX_VDMA_MM2S_DESC_OFFSET;
2864 			chan->config.park = 1;
2865 
2866 			if (xdev->flush_on_fsync == XILINX_DMA_FLUSH_BOTH ||
2867 			    xdev->flush_on_fsync == XILINX_DMA_FLUSH_MM2S)
2868 				chan->flush_on_fsync = true;
2869 		}
2870 	} else if (of_device_is_compatible(node,
2871 					   "xlnx,axi-vdma-s2mm-channel") ||
2872 		   of_device_is_compatible(node,
2873 					   "xlnx,axi-dma-s2mm-channel")) {
2874 		chan->direction = DMA_DEV_TO_MEM;
2875 		chan->id = xdev->s2mm_chan_id++;
2876 		chan->tdest = chan->id - xdev->dma_config->max_channels / 2;
2877 		chan->has_vflip = of_property_read_bool(node,
2878 					"xlnx,enable-vert-flip");
2879 		if (chan->has_vflip) {
2880 			chan->config.vflip_en = dma_read(chan,
2881 				XILINX_VDMA_REG_ENABLE_VERTICAL_FLIP) &
2882 				XILINX_VDMA_ENABLE_VERTICAL_FLIP;
2883 		}
2884 
2885 		if (xdev->dma_config->dmatype == XDMA_TYPE_AXIMCDMA)
2886 			chan->ctrl_offset = XILINX_MCDMA_S2MM_CTRL_OFFSET;
2887 		else
2888 			chan->ctrl_offset = XILINX_DMA_S2MM_CTRL_OFFSET;
2889 
2890 		if (xdev->dma_config->dmatype == XDMA_TYPE_VDMA) {
2891 			chan->desc_offset = XILINX_VDMA_S2MM_DESC_OFFSET;
2892 			chan->config.park = 1;
2893 
2894 			if (xdev->flush_on_fsync == XILINX_DMA_FLUSH_BOTH ||
2895 			    xdev->flush_on_fsync == XILINX_DMA_FLUSH_S2MM)
2896 				chan->flush_on_fsync = true;
2897 		}
2898 	} else {
2899 		dev_err(xdev->dev, "Invalid channel compatible node\n");
2900 		return -EINVAL;
2901 	}
2902 
2903 	/* Request the interrupt */
2904 	chan->irq = of_irq_get(node, chan->tdest);
2905 	if (chan->irq < 0)
2906 		return dev_err_probe(xdev->dev, chan->irq, "failed to get irq\n");
2907 	err = request_irq(chan->irq, xdev->dma_config->irq_handler,
2908 			  IRQF_SHARED, "xilinx-dma-controller", chan);
2909 	if (err) {
2910 		dev_err(xdev->dev, "unable to request IRQ %d\n", chan->irq);
2911 		return err;
2912 	}
2913 
2914 	if (xdev->dma_config->dmatype == XDMA_TYPE_AXIDMA) {
2915 		chan->start_transfer = xilinx_dma_start_transfer;
2916 		chan->stop_transfer = xilinx_dma_stop_transfer;
2917 	} else if (xdev->dma_config->dmatype == XDMA_TYPE_AXIMCDMA) {
2918 		chan->start_transfer = xilinx_mcdma_start_transfer;
2919 		chan->stop_transfer = xilinx_dma_stop_transfer;
2920 	} else if (xdev->dma_config->dmatype == XDMA_TYPE_CDMA) {
2921 		chan->start_transfer = xilinx_cdma_start_transfer;
2922 		chan->stop_transfer = xilinx_cdma_stop_transfer;
2923 	} else {
2924 		chan->start_transfer = xilinx_vdma_start_transfer;
2925 		chan->stop_transfer = xilinx_dma_stop_transfer;
2926 	}
2927 
2928 	/* check if SG is enabled (only for AXIDMA, AXIMCDMA, and CDMA) */
2929 	if (xdev->dma_config->dmatype != XDMA_TYPE_VDMA) {
2930 		if (xdev->dma_config->dmatype == XDMA_TYPE_AXIMCDMA ||
2931 		    dma_ctrl_read(chan, XILINX_DMA_REG_DMASR) &
2932 			    XILINX_DMA_DMASR_SG_MASK)
2933 			chan->has_sg = true;
2934 		dev_dbg(chan->dev, "ch %d: SG %s\n", chan->id,
2935 			chan->has_sg ? "enabled" : "disabled");
2936 	}
2937 
2938 	/* Initialize the tasklet */
2939 	tasklet_setup(&chan->tasklet, xilinx_dma_do_tasklet);
2940 
2941 	/*
2942 	 * Initialize the DMA channel and add it to the DMA engine channels
2943 	 * list.
2944 	 */
2945 	chan->common.device = &xdev->common;
2946 
2947 	list_add_tail(&chan->common.device_node, &xdev->common.channels);
2948 	xdev->chan[chan->id] = chan;
2949 
2950 	/* Reset the channel */
2951 	err = xilinx_dma_chan_reset(chan);
2952 	if (err < 0) {
2953 		dev_err(xdev->dev, "Reset channel failed\n");
2954 		return err;
2955 	}
2956 
2957 	return 0;
2958 }
2959 
2960 /**
2961  * xilinx_dma_child_probe - Per child node probe
2962  * It get number of dma-channels per child node from
2963  * device-tree and initializes all the channels.
2964  *
2965  * @xdev: Driver specific device structure
2966  * @node: Device node
2967  *
2968  * Return: '0' on success and failure value on error.
2969  */
2970 static int xilinx_dma_child_probe(struct xilinx_dma_device *xdev,
2971 				    struct device_node *node)
2972 {
2973 	int ret, i;
2974 	u32 nr_channels = 1;
2975 
2976 	ret = of_property_read_u32(node, "dma-channels", &nr_channels);
2977 	if (xdev->dma_config->dmatype == XDMA_TYPE_AXIMCDMA && ret < 0)
2978 		dev_warn(xdev->dev, "missing dma-channels property\n");
2979 
2980 	for (i = 0; i < nr_channels; i++) {
2981 		ret = xilinx_dma_chan_probe(xdev, node);
2982 		if (ret)
2983 			return ret;
2984 	}
2985 
2986 	return 0;
2987 }
2988 
2989 /**
2990  * of_dma_xilinx_xlate - Translation function
2991  * @dma_spec: Pointer to DMA specifier as found in the device tree
2992  * @ofdma: Pointer to DMA controller data
2993  *
2994  * Return: DMA channel pointer on success and NULL on error
2995  */
2996 static struct dma_chan *of_dma_xilinx_xlate(struct of_phandle_args *dma_spec,
2997 						struct of_dma *ofdma)
2998 {
2999 	struct xilinx_dma_device *xdev = ofdma->of_dma_data;
3000 	int chan_id = dma_spec->args[0];
3001 
3002 	if (chan_id >= xdev->dma_config->max_channels || !xdev->chan[chan_id])
3003 		return NULL;
3004 
3005 	return dma_get_slave_channel(&xdev->chan[chan_id]->common);
3006 }
3007 
3008 static const struct xilinx_dma_config axidma_config = {
3009 	.dmatype = XDMA_TYPE_AXIDMA,
3010 	.clk_init = axidma_clk_init,
3011 	.irq_handler = xilinx_dma_irq_handler,
3012 	.max_channels = XILINX_DMA_MAX_CHANS_PER_DEVICE,
3013 };
3014 
3015 static const struct xilinx_dma_config aximcdma_config = {
3016 	.dmatype = XDMA_TYPE_AXIMCDMA,
3017 	.clk_init = axidma_clk_init,
3018 	.irq_handler = xilinx_mcdma_irq_handler,
3019 	.max_channels = XILINX_MCDMA_MAX_CHANS_PER_DEVICE,
3020 };
3021 static const struct xilinx_dma_config axicdma_config = {
3022 	.dmatype = XDMA_TYPE_CDMA,
3023 	.clk_init = axicdma_clk_init,
3024 	.irq_handler = xilinx_dma_irq_handler,
3025 	.max_channels = XILINX_CDMA_MAX_CHANS_PER_DEVICE,
3026 };
3027 
3028 static const struct xilinx_dma_config axivdma_config = {
3029 	.dmatype = XDMA_TYPE_VDMA,
3030 	.clk_init = axivdma_clk_init,
3031 	.irq_handler = xilinx_dma_irq_handler,
3032 	.max_channels = XILINX_DMA_MAX_CHANS_PER_DEVICE,
3033 };
3034 
3035 static const struct of_device_id xilinx_dma_of_ids[] = {
3036 	{ .compatible = "xlnx,axi-dma-1.00.a", .data = &axidma_config },
3037 	{ .compatible = "xlnx,axi-cdma-1.00.a", .data = &axicdma_config },
3038 	{ .compatible = "xlnx,axi-vdma-1.00.a", .data = &axivdma_config },
3039 	{ .compatible = "xlnx,axi-mcdma-1.00.a", .data = &aximcdma_config },
3040 	{}
3041 };
3042 MODULE_DEVICE_TABLE(of, xilinx_dma_of_ids);
3043 
3044 /**
3045  * xilinx_dma_probe - Driver probe function
3046  * @pdev: Pointer to the platform_device structure
3047  *
3048  * Return: '0' on success and failure value on error
3049  */
3050 static int xilinx_dma_probe(struct platform_device *pdev)
3051 {
3052 	int (*clk_init)(struct platform_device *, struct clk **, struct clk **,
3053 			struct clk **, struct clk **, struct clk **)
3054 					= axivdma_clk_init;
3055 	struct device_node *node = pdev->dev.of_node;
3056 	struct xilinx_dma_device *xdev;
3057 	struct device_node *child, *np = pdev->dev.of_node;
3058 	u32 num_frames, addr_width, len_width;
3059 	int i, err;
3060 
3061 	/* Allocate and initialize the DMA engine structure */
3062 	xdev = devm_kzalloc(&pdev->dev, sizeof(*xdev), GFP_KERNEL);
3063 	if (!xdev)
3064 		return -ENOMEM;
3065 
3066 	xdev->dev = &pdev->dev;
3067 	if (np) {
3068 		const struct of_device_id *match;
3069 
3070 		match = of_match_node(xilinx_dma_of_ids, np);
3071 		if (match && match->data) {
3072 			xdev->dma_config = match->data;
3073 			clk_init = xdev->dma_config->clk_init;
3074 		}
3075 	}
3076 
3077 	err = clk_init(pdev, &xdev->axi_clk, &xdev->tx_clk, &xdev->txs_clk,
3078 		       &xdev->rx_clk, &xdev->rxs_clk);
3079 	if (err)
3080 		return err;
3081 
3082 	/* Request and map I/O memory */
3083 	xdev->regs = devm_platform_ioremap_resource(pdev, 0);
3084 	if (IS_ERR(xdev->regs)) {
3085 		err = PTR_ERR(xdev->regs);
3086 		goto disable_clks;
3087 	}
3088 	/* Retrieve the DMA engine properties from the device tree */
3089 	xdev->max_buffer_len = GENMASK(XILINX_DMA_MAX_TRANS_LEN_MAX - 1, 0);
3090 	xdev->s2mm_chan_id = xdev->dma_config->max_channels / 2;
3091 
3092 	if (xdev->dma_config->dmatype == XDMA_TYPE_AXIDMA ||
3093 	    xdev->dma_config->dmatype == XDMA_TYPE_AXIMCDMA) {
3094 		if (!of_property_read_u32(node, "xlnx,sg-length-width",
3095 					  &len_width)) {
3096 			if (len_width < XILINX_DMA_MAX_TRANS_LEN_MIN ||
3097 			    len_width > XILINX_DMA_V2_MAX_TRANS_LEN_MAX) {
3098 				dev_warn(xdev->dev,
3099 					 "invalid xlnx,sg-length-width property value. Using default width\n");
3100 			} else {
3101 				if (len_width > XILINX_DMA_MAX_TRANS_LEN_MAX)
3102 					dev_warn(xdev->dev, "Please ensure that IP supports buffer length > 23 bits\n");
3103 				xdev->max_buffer_len =
3104 					GENMASK(len_width - 1, 0);
3105 			}
3106 		}
3107 	}
3108 
3109 	if (xdev->dma_config->dmatype == XDMA_TYPE_AXIDMA) {
3110 		xdev->has_axistream_connected =
3111 			of_property_read_bool(node, "xlnx,axistream-connected");
3112 	}
3113 
3114 	if (xdev->dma_config->dmatype == XDMA_TYPE_VDMA) {
3115 		err = of_property_read_u32(node, "xlnx,num-fstores",
3116 					   &num_frames);
3117 		if (err < 0) {
3118 			dev_err(xdev->dev,
3119 				"missing xlnx,num-fstores property\n");
3120 			goto disable_clks;
3121 		}
3122 
3123 		err = of_property_read_u32(node, "xlnx,flush-fsync",
3124 					   &xdev->flush_on_fsync);
3125 		if (err < 0)
3126 			dev_warn(xdev->dev,
3127 				 "missing xlnx,flush-fsync property\n");
3128 	}
3129 
3130 	err = of_property_read_u32(node, "xlnx,addrwidth", &addr_width);
3131 	if (err < 0)
3132 		dev_warn(xdev->dev, "missing xlnx,addrwidth property\n");
3133 
3134 	if (addr_width > 32)
3135 		xdev->ext_addr = true;
3136 	else
3137 		xdev->ext_addr = false;
3138 
3139 	/* Set metadata mode */
3140 	if (xdev->has_axistream_connected)
3141 		xdev->common.desc_metadata_modes = DESC_METADATA_ENGINE;
3142 
3143 	/* Set the dma mask bits */
3144 	err = dma_set_mask_and_coherent(xdev->dev, DMA_BIT_MASK(addr_width));
3145 	if (err < 0) {
3146 		dev_err(xdev->dev, "DMA mask error %d\n", err);
3147 		goto disable_clks;
3148 	}
3149 
3150 	/* Initialize the DMA engine */
3151 	xdev->common.dev = &pdev->dev;
3152 
3153 	INIT_LIST_HEAD(&xdev->common.channels);
3154 	if (!(xdev->dma_config->dmatype == XDMA_TYPE_CDMA)) {
3155 		dma_cap_set(DMA_SLAVE, xdev->common.cap_mask);
3156 		dma_cap_set(DMA_PRIVATE, xdev->common.cap_mask);
3157 	}
3158 
3159 	xdev->common.device_alloc_chan_resources =
3160 				xilinx_dma_alloc_chan_resources;
3161 	xdev->common.device_free_chan_resources =
3162 				xilinx_dma_free_chan_resources;
3163 	xdev->common.device_terminate_all = xilinx_dma_terminate_all;
3164 	xdev->common.device_synchronize = xilinx_dma_synchronize;
3165 	xdev->common.device_tx_status = xilinx_dma_tx_status;
3166 	xdev->common.device_issue_pending = xilinx_dma_issue_pending;
3167 	xdev->common.device_config = xilinx_dma_device_config;
3168 	if (xdev->dma_config->dmatype == XDMA_TYPE_AXIDMA) {
3169 		dma_cap_set(DMA_CYCLIC, xdev->common.cap_mask);
3170 		xdev->common.device_prep_slave_sg = xilinx_dma_prep_slave_sg;
3171 		xdev->common.device_prep_dma_cyclic =
3172 					  xilinx_dma_prep_dma_cyclic;
3173 		/* Residue calculation is supported by only AXI DMA and CDMA */
3174 		xdev->common.residue_granularity =
3175 					  DMA_RESIDUE_GRANULARITY_SEGMENT;
3176 	} else if (xdev->dma_config->dmatype == XDMA_TYPE_CDMA) {
3177 		dma_cap_set(DMA_MEMCPY, xdev->common.cap_mask);
3178 		xdev->common.device_prep_dma_memcpy = xilinx_cdma_prep_memcpy;
3179 		/* Residue calculation is supported by only AXI DMA and CDMA */
3180 		xdev->common.residue_granularity =
3181 					  DMA_RESIDUE_GRANULARITY_SEGMENT;
3182 	} else if (xdev->dma_config->dmatype == XDMA_TYPE_AXIMCDMA) {
3183 		xdev->common.device_prep_slave_sg = xilinx_mcdma_prep_slave_sg;
3184 	} else {
3185 		xdev->common.device_prep_interleaved_dma =
3186 				xilinx_vdma_dma_prep_interleaved;
3187 	}
3188 
3189 	platform_set_drvdata(pdev, xdev);
3190 
3191 	/* Initialize the channels */
3192 	for_each_child_of_node(node, child) {
3193 		err = xilinx_dma_child_probe(xdev, child);
3194 		if (err < 0) {
3195 			of_node_put(child);
3196 			goto error;
3197 		}
3198 	}
3199 
3200 	if (xdev->dma_config->dmatype == XDMA_TYPE_VDMA) {
3201 		for (i = 0; i < xdev->dma_config->max_channels; i++)
3202 			if (xdev->chan[i])
3203 				xdev->chan[i]->num_frms = num_frames;
3204 	}
3205 
3206 	/* Register the DMA engine with the core */
3207 	err = dma_async_device_register(&xdev->common);
3208 	if (err) {
3209 		dev_err(xdev->dev, "failed to register the dma device\n");
3210 		goto error;
3211 	}
3212 
3213 	err = of_dma_controller_register(node, of_dma_xilinx_xlate,
3214 					 xdev);
3215 	if (err < 0) {
3216 		dev_err(&pdev->dev, "Unable to register DMA to DT\n");
3217 		dma_async_device_unregister(&xdev->common);
3218 		goto error;
3219 	}
3220 
3221 	if (xdev->dma_config->dmatype == XDMA_TYPE_AXIDMA)
3222 		dev_info(&pdev->dev, "Xilinx AXI DMA Engine Driver Probed!!\n");
3223 	else if (xdev->dma_config->dmatype == XDMA_TYPE_CDMA)
3224 		dev_info(&pdev->dev, "Xilinx AXI CDMA Engine Driver Probed!!\n");
3225 	else if (xdev->dma_config->dmatype == XDMA_TYPE_AXIMCDMA)
3226 		dev_info(&pdev->dev, "Xilinx AXI MCDMA Engine Driver Probed!!\n");
3227 	else
3228 		dev_info(&pdev->dev, "Xilinx AXI VDMA Engine Driver Probed!!\n");
3229 
3230 	return 0;
3231 
3232 error:
3233 	for (i = 0; i < xdev->dma_config->max_channels; i++)
3234 		if (xdev->chan[i])
3235 			xilinx_dma_chan_remove(xdev->chan[i]);
3236 disable_clks:
3237 	xdma_disable_allclks(xdev);
3238 
3239 	return err;
3240 }
3241 
3242 /**
3243  * xilinx_dma_remove - Driver remove function
3244  * @pdev: Pointer to the platform_device structure
3245  */
3246 static void xilinx_dma_remove(struct platform_device *pdev)
3247 {
3248 	struct xilinx_dma_device *xdev = platform_get_drvdata(pdev);
3249 	int i;
3250 
3251 	of_dma_controller_free(pdev->dev.of_node);
3252 
3253 	dma_async_device_unregister(&xdev->common);
3254 
3255 	for (i = 0; i < xdev->dma_config->max_channels; i++)
3256 		if (xdev->chan[i])
3257 			xilinx_dma_chan_remove(xdev->chan[i]);
3258 
3259 	xdma_disable_allclks(xdev);
3260 }
3261 
3262 static struct platform_driver xilinx_vdma_driver = {
3263 	.driver = {
3264 		.name = "xilinx-vdma",
3265 		.of_match_table = xilinx_dma_of_ids,
3266 	},
3267 	.probe = xilinx_dma_probe,
3268 	.remove_new = xilinx_dma_remove,
3269 };
3270 
3271 module_platform_driver(xilinx_vdma_driver);
3272 
3273 MODULE_AUTHOR("Xilinx, Inc.");
3274 MODULE_DESCRIPTION("Xilinx VDMA driver");
3275 MODULE_LICENSE("GPL v2");
3276